I wouldn't have switched your cam sprocket...wear items need to stay together as a matched set, chains and sprockets in this case
I would have kept the cam box, end caps, cam, rockers, rocker adjuster pins all together, form the 72 and used the cam chain and sprocket from the 69
I would have also picked the best cam chain tensioner and guide parts from the two,
how were the valves? did you test them? to see if they leak?, how are the valve guides?...any play?
did you set the valve lash properly? did you set the cam chain adjuster properly?
did you measure the cam end play and get it within spec?
did you make sure the oil passages are clear and not blocked by improper gasket placement?
all of the above will add to noise