I looked at that gear and im impressed.> my thoughts are that 14 by 1.25 sounds to fine for an aluminum block. I would have thought the 14 by 1.5 would have been correct. Anyway you should pick up a plastic universal thread/bolt hole gauge somewhere with the hole sizes in it. I like it 10 times more than the metal jackknife type thread gauges, I rarely use those.

Anyway nice find there> can you tell us how it fits? looks like it should clear the skid plate.