The seat pan is key.
If you want to try to install car seats or whatever, the pan gives you a level platform to fit them to rather than the bumpy truck floor.
I have snagged a few of the pans and put them in a couple of trucks and shipped one off. You can even use the floor frame from the Ford "Show Trucks". They were aftermarket conversion companies that installed custom seats. The made a level skeleton frame out of 1x1 square tubing.

The pan and aftermarket frames essentially use your factory seatbolt locations of the bench seat you have in your truck and allow for more stable seat mounting in the middle of the truck floor. You also do not weaken or have to make a bunch of holes in the cab floor in case your seat plan doesn't work out as you like.
You can put your bench seat back in the truck and no one will ever know you had rigged some type of seats in the truck.

 

I understand about the seat pan, that is a great suggestion and I will look that way if I find some decent seating . 90s trucks mostly have destroued or delapidated seats as you stated 4/4 seats wear on the end, i see that in my truck and it only has 67000 miles on it. Oh and my truck is The Golden Girl, i am a man , men dont name their trucks or cars male names they give them female names because they are beautiful to the eye.

 

I have had success with the small ford explorer bucket seats in a couple of trucks. Very comfortable and plentiful in the junkyards.
Full power and lumbar. Can adjust to any height and will fit without using the said seatpan. Very easy to install.

 

This will be my next project in a couple of weeks. I just picked up a 96 swb 4.9 to get back to ENC from Texas on Christmas Eve. I'm DD'ing it now and I just have to say the seat is absolute crap (i'm sorry for the language, its polite compared to my more private descriptions) I was going to swap out the bench seats with my '83, figuring it should be relatively simple, but in the past 9 months that she has been parked a family of mice have decided to prepare for winter by feasting on my big, cushy (and heavenly by comparison) bench from my beloved 83.

So, a long story even longer, the blow I took having my dreams dashed has been lessened considerably by all of the options that I have found on our fine website.

I'm sorry for the thread hijack, just needed to make a joyful noise. I don't know if i'm more excited about my future rear end comfort or nervous breakdown I will surely avoid by having CUP HOLDERS in the future!