Honda-SOHC

Recently acquired a 1972 cb500 four, a bike I have know for a long time from the original owner, and will be doing a bit of light restoration on it as generally it is good, it has a 4 into 1 which is growing on me but would like to put the 4 pipes back on as that's what I remember from when the cb500  and the cb750 came out. I have the original purchase receipt and brochure for it.
Tank needs a respray then good enough for me. Only other Honda I have is 1967 p50 moped the one with the engine in the back wheel.