Sounds like your not far off in primary engine pump timing except for the nailing sounds. They are not cam related in my opinion. I do not expect that they made any radical grind cams for these engines anyways Also not sure whats disturbing you exactly. Is it the overall sound of the engine. You might try retarding the pump a little and see if it sounds better and power is still adaquate. On the otherhand since it is old if you have never had the injectors pop tested perhaps its time. Beyond a certain age we are entering the world of restoration more than just simple repair. More like actual restoration and I have been mentally experimenting with ideals to test things with home methods that are cheap, hopefully accurate and conclusive. They are really in the primative stage and will take quite awhile to work out but everytime I hear of a situation like yours I can see the applications if viable. Other than that it's pretty well live with it or spend money. I never seem to lack a place to use the money saved by using unorthodox methods to some extent. Just my methology and not for everyone.