Talk to me about this- long story short- pulled my distributor to diagnose an oil leak (no O-ring, thanks PO) and lost alignment. Re established TDC using the mark on the flywheel. I see the slot at the bottom of the distributor hole, and the bottom of the distributor sure looks like it is designed to engage, but when I put the engine at TDC and the distributor rotor aimed at the #1 spark plug wire, that tab on the distributor does not align with the slot. Also, that slot does not rotate when I crank the engine around. How do I know the distributor is fully seated? Is that tab on the end of the distributor supposed to engage with that slot? New here so hoping someone can help me out. 1976 2F engine.