i found a 351m that has a 2 bbl intake can i put a 4 bbl intake on it? thanks :rebelflag

i found a 351m that has a 2 bbl intake can i put a 4 bbl intake on it? thanks :rebelflag

i just bought an 1980 bronco and it has a big block bell housing. so heres the question which motor do i put in it a 351m or a 400? :wtf how do you tell the 351m and 400 apart from the other big blocks? if im buying one from a salvage yard what do i need to look for problem whise? thanks any...