can anyone tell me the model code

[tworiversuk]

it was registered IN THE uk on 19-03 80,making it a 'V' registration, engine number ;CB750E-2736355   FRAME NUMBER ;CB750K-2735369 ,color excel black, oil tank hidden behind side panel, 17" rear wheel,according to this info it's a 1977 but registered late in 1980 , but still a K7
http://www.sohc4.net/index.php?title=CB750K7

[SteveD CB500K0]

392 or 405 according to this:

http://www.dropbears.com/m/models/honda/modelcodes.htm