1968 Dodge D200 with a 318 from who knows where

Yeah, I question the legitimacy of the theory, that because the engine is internally balanced, you don't need a dampener on it, myself. If I understand the dampening affect of the harmonic balancer, having the rubber and the steel outer ring on the balancer/dampener, sure can't hurt.
The issue I have is, if I go buy a new harmonic balancer (which I did) from the local auto parts place, I get one with the timing marks that would work if you had a timing chain cover with the timing marks on the drivers side. I can put a mark on the new harmonic balancer just based on matching the degree or angle of the existing harmonic balancer. I could try installing a new one and see if there's any interference issues that I can't see while everything is still in pieces.

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