First, the missing part is the pto clutch, not too hard to find. The parts still on there, the disk and little half circle clips are hardest to find items when you buy one. It has the pulley's on it and the surface for the disc all in one. Then there is the rods and links needed to use it, which go back to a lever on the right of dash tower.Take that back, the rod and link is there, just the up/down rod that runs clutch is gone. I've not heard of an 8 model?? there is B-80's and B-800's all pretty much same tractor. This one is only four speed, so must be early one. Others may have the dual range 8spd. Many times the 4spd will slip out of high gear (really just 3 with reverse) when under load. Make sure it shifts. These are neat and easy to work on tractors. BUT, I'm thinking .30 /lb can add up real quick, not be worth it. I have bought similar for $50 to $125 and needing tear down and work like this will. Don't know weights right off. If engine is all stuck will be most expensive build part and might wanna pass. Lots of wheelhorse around, not that hard to find and usually cheap.