Another thought instead of carpet is to get some of the roll on bed liner to put on the floor.? It has alot of pros; such as sound proofing, durable, doesn't trap smells, and if applied the right way resembles carpet and a heck of alot easier to clean.
I know early 90's 4skinner front bucket seats are a bolt in and have pretty good butt and back support with ability to put in a custom center console or just more room to reach behind you. I definitaly like them in my std cab p/u for the extra room and support when sitting in them all day long wheeling or driving down the road.