I started installing the ACC vinyl floor cover in my 82 yesterday. Spent around 2 hours removing the seat and seat belts, and cleaning up the floor under the seat. A previous owner must have driven the truck down dirt roads for years with the windows open! Someone had also glued down a thin piece of black felt to serve as a carpet, and the glue caused the paint to peel. Fun stuff!
Anyway, when I first dropped in the new floor cover, I thought, "No way will this fit." However, I eventually got it positioned so the molded-in contours of the vinyl fit the floor almost perfectly. The problem was the cover is 8"-10" longer in the front than it needs to be, so must be folded back on itself for the rest of the cover to fit the floor contours. I also unbolted the accelerator pedal from the firewall to push the vinyl in behind it.
After I got that far, I trimmed the left and right sides, and then screwed down the door thresholds to hold the cover in place. Now I'm working on the front edge under the dash. In an ideal world, the heater box would be removed for floor cover installation, but I had just repaired and reinstalled it a couple months ago, and don't want to remove/replace it again.
On another note, a friend gave me a couple sheets of HushMat Ultra that I installed in smaller pieces on the floor under the seat, I am also using the pre-cut ACC-supplied jute backing, which covers the foot wells (top of sloped section to front of seat). Somewhere down the line, I'll probably install more sound deadening material and may replace the jute with a cotton/foil heat barrier like this:
http://www.bondedlogic.com/ultratouch-radiant-barrier/
By the time I get the cover fully installed and the seats and seat belts back in place, I will probably have 6-8 hours in the job, which includes cleaning and prepping my dirty floors.