[67ConvFB]

Short block means just the bottom end of the motor. Long block would be the bottom end with atleast the heads included. Any 400 will fit, but I would try to find one from 67 to somewhere in the mid 70' s. I put a 78 400 in a 66, and had to drill and tap one side for motor mounts, and had to fabricate an adaptor for the other side because there was no bosses to drill and tap. Sorry, I don' t know what year they started leaving these bosses off, but it was in the late 70' s. Hope this helps.