Most of us live our happy motoring lives with the factory-installed interior. Sure, at some point you may throw on a set of sheepskin seat covers or stick one of those Hula Girl bobble dolls on the dash, but otherwise, you're riding showroom stock.

And no wonder, customizing interiors can be incredibly expensive and ferociously labor-intensive. But if you are already restoring a 1957 Chevy, you might as well upgrade the interior with modern seats and materials. Sure, restoring a car to its original showroom look is admirable, but the results are not very comfortable.

Car enthusiasts with money to show off take things several steps further, by ripping out perfectly good new interiors of $100,000-plus cars and customizing them in outrageous ways. Granted, some of them are very cool and worth their weight in Alcantara. Others, not so much. Here are ten really well-done interiors and five that are truly awful.

15 A True Work Of Art

Beautiful resto-mod interior

A big pat on the back to Customs and Hot Rods of Andice for creating this masterpiece of subtle luxury. The fifties-era car is almost unrecognizable as being more than a half-century old thanks to all of the grand work. From the door panels to the cool design on the seat cushion, this interior knocks it out of the park.

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14 Smooth Operator

57 Chevy Belair Custom Leather Interior

Man, do those seats look comfortable. A meeting of modern and retro, the creme-colored custom interior in this 1957 Chevy Bel Air is clearly for someone who never gets their hands dirty. The chrome accents are used sparingly, giving the whole thing an understated elegance. This no-expense-spared custom work is show quality, for sure.

RELATED: 10 Inexpensive Everyday Cars With Luxurious Looking Interiors

13 Leather-Bound And Determined

The custom interior of a car named "Sonny"

The unique choice of seamlessly marrying two (generally) opposing colors - a somewhat natural-looking brown cowhide and a modern slate gray - really works for this custom interior. Even the steering column matches the rest of the gray touches throughout. The leather-covered dashboard is a great point of reference for the superb stitching.

RELATED: 10 Inexpensive Everyday Cars With Luxurious Looking Interiors

12 Blowing Off A Little Steampunk

Ricardo Valero pinned this custom interior on Pinterest

These seats almost look too comfortable. It is probably the camera angle, but those buckets are made for absorbing the powerful g-forces generated by that engine sticking out through a hole in the hood. The gauges seem like a bit of an afterthought, but we see what they were going for there.

11 Land Of British Royalty

Rich leather upholstery of a Land Rover Defender

This Land Rover Defender has been decked out to the max with matching leather inserts throughout giving this high-brow 4x4 a healthy dose of opulence in all of the right places. The hides work well with the normal black dash, steering wheel, and other interior bits. Expect your arm to fall asleep on that cushy center console armrest.

10 Rich Mahogany Leather

A custom interior by Classic Car Studio

From the interior wizards at Classic Car Studio comes this exquisite pairing of animal hides and hardwoods. By the shape of the windows, this vehicle appears to be a '50s-era Chevy. The seats look like extra comfy. The overall effect is one of a cozy living room. All that is missing is the fireplace.

9 Blinded By The White

Blinding white interior of a 2012 Mercedes-Benz CL 800 Coupe

OK, the white is a little much, but this interior is still a work of modern art. With bold diamond-shaped lines and no-expense sparred materials, this custom 2012 Mercedes-Benz CL 800 Coupe interior screams disposable income. And that Alcantara-wrapped steering wheel looks like a dream to use. No eating in the car, kids.

8 We Don't Need No Stinking Floor Mats

1967 Chevy C10 custom interior

We spied this custom work over on Pinterest. Believe it or not, this is a 1967 Chevy C10 pickup truck. The straight-as-an-arrow dash is a little awkward, especially the 9-inch screen that is framed in different color material. The super shiny chrome strips on the floor scream for floor mats. Still amazing.

7 Definitely An Inside Job

1958 Corvette interior job. auto upholstery grey with brown and tan

This show-stopping interior is part of an immaculate 1958 Corvette that has been given a no-expense-spared resto-mod for the ages. The dashboard is absolutely insane. They did an amazing job of incorporating the leather into the shapes of yesteryear. Notice the power window controls and sound system upgrades. Traditionalists will not be amused.

6 This One Will Have You Seeing Red

Mercedes-Benz SLR with a very red interior

Someone went hog wild with this Mercedes-Benz SLR interior. While it looks fantastic and is of the highest quality, you must be a fan of the crimson shades to fully enjoy this ride. The black steering wheel looks almost like it is floating above the red sea of leather. Tasteful, yet only for true fans.

5 (Sickening) Tesla Model Ass

The worst custom Tesla Model S interior ever (Reddit)

If Steve Irwin was still alive, we imagine his Tesla Model S would look something like this. Nothing says "car of the future" like a pile of dead animal skins laying on the dashboard. Once you see this crime against taste and decency, you can never UN-see it. Elon Musk, please make it stop.

4 (Sickening) Orange You Unimpressed?

Orange Gator Skin interior
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Hey, Crocodile Dumbdee, do you think the alligator who gave his life for these seats inserts would appreciate what was done here? Good luck keeping that white leather clean, dude. And, if you are going to dye some gator skins orange, at least match the exterior paint color a little better.

3 (Sickening) What Is The Opposite Of Green With Envy?

Nissan GT-R custom interior in lime green with black hexagon stitch

Is this awful lime green and black custom interior from a Nissan GT-R the worst thing in the world? Not even close. But it is still too much for the average driver, for sure. The hexagon stitch is cool, however, especially how it is represented in both colors. But no, this is bad. Very bad.

2 (Sickening) Are The Vomit Bags Blue Or Yellow?

2010 Mansory Porsche Panamera Power Pack

Look what Mansory did to this 2010 Porsche Panamera. Just look at it. On second thought, don't. This interior has the feel of a Transformers movie - we just wish that it would transform into something good. And what is up with those black floor mats? They ruin what was a perfectly terrible color scheme design.

1 (Sickening) Steering Wheel Of Misfortune

Sorry E3 Customs, we don't like the wheel

That steering wheel is absolutely ludicrous. You might be thinking, well if it's just the wheel, it's not so bad. Look closer and you can see that there's an awful puffy cloth covering the dash that is damn near impossible to clean. None of this will age well. In two years this interior will be complete junk. Happy motoring.

Sources: Pinterest, Customs and Hot Rods of Andice, Classic Car Studio, Overblog, Interior Shot, E3 Customs, Reddit, Carnity

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