???
It is not just an issue of the clutch housing being able to bolt to the engine/block. The donor clutch housing should match the style for the year of the recipient truck. (Yakimabowtie's question is pertinent.)
The 1953 and earlier truck 216/235 clutch housing has a different motor-mount angle (and different motor mounts) from the 1954 and later 235/261 truck's clutch housing.
Also, I think that some 261 clutch housings might have been set-up for a hydraulic clutch (and maybe the throw-out bearing fork on the opposite side)? I dimly recall that I could not use my 1960 big-truck 261's clutch housing in my 1954 1/2 ton truck.
Brian, did your 55 truck not come with a clutch housing??
