[skidmarks]

Im guessing from pictures, the second bolt hole was that the adapter worked on another engine.

I also noticed that the slotted indexing holes varied , some have a few like the one at the beginning of this thread and others looked like the have one every 15 degrees or so. Im sure over the years when they were msde there were a lot of changes

I was looking for the length of the legs thinking the large end would be made first because it indexes in the yoke and the rear of the engine floats in the rear yoke