When I was 15, the first vehicle I bought was a ****** CJ3A that someone had swapped an olds 215 into. Boy did we have fun. Sold it after a few years to get something “more practical”. Well, 53 years later I decided I had to do it again. Found a real clean 99 Jeep Cherokee 2 door and an Olds 330. Took the Olds to the bare block, thoroughly cleaned and reassembled. New timing cover, water pump, lifters, reconditioned cylinder heads and I rebuilt the Qjet. Edelbrock manifold. Fired right up, runs great. My reason for posting is the following.
I first thought I’d use an automatic, but my kids would hear nothing of that. Ok, got the Novak adapter for Jeep AX15 into GM Bellhousing.
Even found an original Olds flywheel ( yes, 64-67 style). But oh, no pilot hole! So I read all the posts about how not to try to drill the crank in the engine. Well I happen to be lucky enough to have a great friend who is a machinist and, with his help, there is a way! Take a 2” round hunk of steel bar and turn one end down to 1.70 to fit the torque converter recess in the crank. Drill the center to 1/4”.






If you should proceed this way just be sure the first drill(1/4”) is carbide. We enlarged by 1/8” increments up to 5/8”, then by 1/16” up to
15/16. The AX 15 uses a pilot bushing 3/4” ID, 15/16” OD. This method is only recommended for those silly enough to not want to take the crank out again and send it to a machinist. But it does work.

 

This might work well enough for your situation.

 

Neat process. How did you ensure/keep the drill at the proper angle?
Did you put a dial indicator in the hole after to check trueness?

 

The drill guide was a very snug fit in the torque converter recess. As in the picture, we used a clamp on either side to prevent any movement
while drilling. After installing the pilot bushing we mounted the trans/ Bellhousing without the clutch. Trans in 4th gear. Able to spin the output shaft with no resistance

 

Coincidentally, I am facing the same situation and have opted to at least try to properly drill my crankshaft while installed. Like yourself, I’ve turned a piece of solid stock to the correct ID of the converter hub. I left out of country for the duration of this month, so that was all that I was able to accomplish. When I return, I’ll be center drilling and cutting off incremental drill guides to create a relief for the transmission input. Depending on how successful I am, I may continue until I’m able to ream the hole to the correct diameter. It is the exact same process that you are using. Keep us posted on your progress and results. I’m really looking forward to getting started.😀