Changing the seats depends on how much work you want to put into it. I say this beacuse if you pull the bench seat you will also have to cut out the seat frame from the floor board to install a differnt kind of seat. I installed a set of leather power/heated bucket seats out of a 99 Acura in my 50 5 window. I believe it was well worth the work. The truck is very comfortable to ride in. And my wife loves it because she can adjust the seat to where she wants it. here is some pics of the truck and the seats installed. I also modified the Acura console to fit between the seats very handy.
http://inlinethumb48.webshots.com/49647/2363061540107361323S600x600Q85.jpg http://inlinethumb41.webshots.com/51240/2665630340107361323S600x600Q85.jpg As far as the 12v conversion goes, get a alternator with a internal volt regulator, less clutter on the firewall. And make sure to have real good grounds from the engine to the frame and firewall to the frame. And especially battery to frame ground.
