Which cab configuration is either truck? A single cab with a bench seat won't have the two inner holes for buckets/captains chairs. As far as putting power seats in a truck that doesn't have them, you're probably going to need to run wiring from the donor truck. I'm not sure if the w/t would have a connector somewhere in the dash harness for the seat wiring or not, I kinda doubt it. Personally, I swap out power seats for manual. Seat motors are way too slow and a pain in the ass when the battery is dead. It can't be too complicated to wire up yourself tho if that's what you'd like to have.
Value of a Jasper? Where in PA are you? I tend to shy away when I hear "Jasper" as I've heard too many horror stories about they're rebuilds. I don't have any firsthand experience to tell you the truth. I had to buy a vortec 5.7 last year and most junkyards around here in eastern PA wanted $8-1200 for a low mile motor with a 30 or 90 day warranty. I took the cheaper route and spent less than half that amount on a rotted to **** 1 ton express van, pulled the motor, sold the cats for more than I paid for the entire van and then over the scale it went.