I would not cut the cam. the 180 degree cam I have here was ground down and welded up to a new lump and then ground to the right specs. Megacycle can do that for a very reasonable price. If you go that way, choose their street (mild) grind. It's better than their race cam on our small motors at low revs and loses nothing at the top end.
BTW, 180 degree motors make more top end and less mid and low range. 360 motors make more bottom end. Or so teh data that Honda published on teh CB and CL 77/72 motors says.
Focus on compression ratio and combustion efficiency including good fuel atomization, and of course friction/weight reduction.
160 end cap is fine. IRRC the 200 head has different oiling, so check that oil is getting to both end journals and it will be fine. You can grind down the soft cam journals and slip on hardened sleeves and then fit needle rollers in the end caps (towers).
Personal taste, but I'm not feeling that wheel color.