I put a set of bucket seats out of a Dodge Neon in my M109.......I loved them...they took a lot of the rough out of the ride. I sold the truck the Lamar Rowland and he kept them in the truck.
Just about anything beats those old box seats.
I plan on installing the same kind in my M275 Tractor, my last cargo deuce and if I bob another one, I'll put them in that too.
It was nice to have more adjustment than the stock springer or box seat.
I used 1" square tubing, 3/4 inch galvanized pipe, all thread and a lot of "Redneck Engineering to get them in there right.