99-05 tahoe, suburban, yukon, silverado seats work great, and they also have built in seatbelts for pre-'66 trucks.
I used '99 tahoe second row 60-40 seats in my '56--lower back than front seats so don't stick up above the window, seat bottoms flip up, backs flip forward, uneven mounting led me to use old rubber motor mounts and washers to even things our without reinventing the mounts.
