Uugh! 1 inch long green and orange shag carpet, top to bottom, side to side...
The worst thing I ever did was break a bottle of garlic flavored olive oil in back. That smell lingered for years. On sunny days you could smell that truck from a block away. YEARS!!!
I feel ya, I worked as a butcher for two years in a supermarket, and my pants, and boots spread the work stench to every fiber of my car's interior. It was like the smelly car episode of Seinfeld, no matter what I did, no matter how much cash I spent on carpet treatments, the smell still lingers in tat car.
... a switch to turn off all lights, brake lights, turn signals etc. Total blackout. We use to play 4 wheel hide and seek at night in a large area that had hills, fields and tons of trails that crossed over each other etc....
I've got my Pain(full)less harness stretched out on the ground right now, and I was thinking about how to wire in a blackout switch, just to mess with tourists at night as they're going up the windy roads I live off.
4X4 hide and seek is really an awesome idea, though.
For me, it's a toss-up between hacking the dash for a radio that ceased to exist likely long before I ever bought the rig, haphazardly installing a fourth gear into my 3-speed tranny, which just about killed it, tapping the ignition coil for the electric fuel pump, dropping Jeep seats onto the old seat frames. (Literally dropped, no welding involved, anywhere.), or the shiny electric-purple butterfly sticker in the back window that said: "self-esteem".
Regardless, I love my 40, and I'd gladly deal with all these problems again just because it's the car of my dreams.