I posted awhile back about trying to restore my 88, 4 door. It is a frustrating adventure.
I bought my carpet from ACC/ Factory Interiors. It is impossible to get a good fit due to wrinkle at the driver side wheel well.
It will not lay flat or fit with trim pieces.
Super disappointed right now.

 

They typically will fit quite well, eventually. If it is wrinkling, the pre-molded sections aren't aligned with they're body panel yet. It seems they need to go a little farther forward, up under the dash, than you would think, but if it is just the driver's floor, it is probably rotated slightly as well. Tip number 1: Cut the carpet down the center to the rear end of the e-brake, this will be under the console anyway and it will help the carpet lay more naturally where it needs too (you do have a console, right?). Tip number 2: Use a heat gun (not too hot) on the backside to help it conform (or just lay it in the sun for a while). Tip number 3: Get it as close to "in place" as you can. Put the side trim in. Mark the carpet at the trim with chalk. Remove the trim and cut the carpet up close (like an inch) to the chalk mark, removing what is binding/bunching behind the trim.
For style points, use an awl to find the holes for the seat fasteners, mark the holes with chalk, use a straight soldering iron to make the holes for the fasteners. This will cauterize the hole so it won't "run" later and it is easier than most other methods of cutting the holes (kinda stinks, but the iron will clean).

 

Thank you for your pictures.

 

The front is going in pretty good.
The back by the wheel well and gas filler is a bad mess.

What is that yellow box hanging from your dash?

 

Now I feel like an idiot sending pictures. I think that is the wipe delay electronics. I sure thought you meant front wheel well.

 

I'll send you my thoughts (and maybe a picture) of the filler neck/spare tire/wheel well area tomorrow. It may not be that uncommon that you are struggling there.

 

Thank you for the pointers, especially burning a hole instead of cutting.

 

I’m forced to admit my error, the front wheel wells don’t even contact the passenger cabin. So, the rear wheel well… I no longer have purchase info on the carpet I installed. I too had difficulty behind the left rear wheel well. At the time no one, on forums or YouTube, had complained about the fit at that area so I reasoned that I had ordered a carpet that was intended to fit a vehicle with a tailgate mounted spare tire and the sheet metal was different on mine with the internally mounted spare tire. Perhaps this is not the case.

If you’re experiencing what I did, there isn’t enough material to span between the trim at the tailgate and the rear third of the wheel well without it puckering from behind the side trim. To make it “work” I took the excess carpet that I cut from the back of the carpet piece (that extends past the tailgate trim) and cut it to fit around the filler neck and back third of the wheel well. I applied, glued, these patches to the filler neck and wheel well from just behind where the trim covers and out onto the floor of the cabin, maybe 4 or 5 inches. With several pie shaped cuts these pieces will fit fairly well.

With the rear carpet piece back in place, I then started to fit in the trim – which wouldn’t fit. I started slicing the carpet at the places it was coming up short until the trim would install in to place. I used a small brush to apply the contact cement to hold the loose ends of the carpet down.

I would not do this if I didn’t intend to install the spare tire. It is nearly unnoticeable with the spare tire in place. It would not be acceptable without it.

And yes pictures, but I didn't take any pictures of how crappy it looks without the spare tire: