Off the top of my head:
--rearsets
--slimmer tank (4.5gal v 5.1)
--different seat, cowl
--dual front discs, rear disc (vs single front, drum rear)
--dual horn
--slightly different gearing
Later F model heads (including the '78) had problems with valves/valve guides wearing fast. A common solution is to put the same year head from a K engine (the "regular" one).
What's the asking price?