True. The 50 frame would almost be the same as the 51 except for a few holes needed to mount the 51 support brackets (see attachment). I don't know if the 50 slide/track and the fixed "C" bracket on the second cross member would need to be removed. If someone tries this, please take pictures.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
