A "heads-up" for your future work so you don't have a heart stopping moment. You'll get to a point where you are about to install the cams and realize the cam-chain is on the wrong side of the water-pump/ignition timing gear.
AND.....You were POSITIVE it was correct when you did that part of the assembly! The cam chain has a propensity to do this on it's own, very easily! . Getting the chain back to the front side of the gear is a matter of holding as much slack chain as you can get above this gear and jiggling it up and down until it gets around "the tight spot".
That shiny line in the cam-chain well is a mould line. Ironically it this were not there the cam chain would slip back into place with no effort.
Whilst on the topic of "Having a Moment": - These little buggars sit on top of the CCT sprocket shaft. The moment you start to lift the cyl.-head they will make every effort to fall out and drop into the oil pan ! Remove them immediately and do not install them until the last moment before replacing the head.