Would a set of front 04+ F150 seats fit in my 02 single cab?
I have an 04 as well, and the seats seem a lot bigger than in my 02.

 

get a tape measure and measure the actual size of the seat and see if it will even fit in there and leave you with room to breath, and if you really want to go through with it then start measureing the rails they sit on and the mounting holes to see how you could mount them in your truck

 

The Floor is different. You'd need to make custom mounts.