The position of the pipes tg. Didn't occur to me that it might be a 500, so I could also easily be wrong. The 700 also had pipes positioned similarly, but they are even rarer beasts. I don't usually pay much attention to the paint jobs, look at how many Daytona CR paint jobs are around, on non CR750's.
Did go back and look at the picture, after your post, and the tail isn't right for an early 750, so you may very well be right. That said, body work was constantly changing, and that bike also has an alloy swingarm. It was the frame, shock, swingarm setup that prompted Syscrush's post, and got my attention. Maybe Syscrush will chime in, with more details on the bike, then we can find out for sure.
Fast Freddie was one of my hero's (and rode Honda's), along with Barry Sheene, when I was growing up. It was the people, not so much the bikes, that fascinated me back then. Had a Arai FF replica helmet for a long time. Was going to buy one of the new AGV Sheene replica helmets (their beautiful), until I got a deal on an Arai Phil Read.
The Arai's fit me perfectly, so that tipped the scale.