will a dohc engine fit a sohc frame

i guess that is what i was trying to figure out in a previous posting. pretty excited go my first bike project love the way the cb's look and ridei got a titled frame for a 73 sohc cb750 and a dohc 750 from an 80 my hopes are to be able to mate the two and build a fun bike other wise i will use the titled remains of the 80's frame for a chopper project.  any help would really be appreciated i will keep updates from time to time and upload photots.

ciao max