Nice project there Steve. I rode my first CB750 when I was at Navy College back in 1975...the owner also had a Kawasaki 750 H2...which scared the bejesus out of me.
The owner of the 'N' reg CB750 that was at the pub on Thursday evening had that blue paintjob which he said was all original...as was the chrome.
But I do think that UK Pete's K1 has the most character as it looks used in it's unrestored condition, & is a good example of how a bike should be used. A comment that I heard on Thursday about the pretty CB500/4 was that it wasn't original as too much of it was polished, as in the clutch & alternator cases were too shiney.