Following Bob's lead and using the tools he loaned me, I made two engine block ground points using the pre-drilled holes already in the engine block. I will probably only use one ground point, but the other one will be there in case it's needed as it was easy to make the second one with the engine still off the airframe. I drilled the holes out to 5/16", countersunk to 82*, and tapped them for 3/8"-16. Bob sent me an alignment jig to drill the hole on one side and tap perpendicular threads on the other. I drilled the hole with the jig, sanded the paint off with the sander, then used the other side of the alignment jig to tap the hole. I still took my time and did not rush; tapping threads in the engine block is a "failure is not an option" operation, and you need to get it right the first time.
