Need 318 Gurus

... You run the vibration damper that is matched for the crank... If the timing marks are off, just put the engine at TDC and make a mark on the damper to match the marks on the timing cover/timing tab... That way the motor keeps its proper balance.... It's easy to re-mark the vibration damper for the different location if needed...

That is one way to do it. But since it is going in a 75 Trailduster and they are both 318's, I'd swap the timing cover, damper, and all the brackets from the blue to the orange and be done. I'd still find true TDC while it is out and verify the mark.