Cam swap without pulling motor

I’d calculate how much milling would be required to get it to 9:1.
Personally, I wouldn’t go nuts with that.
I wouldn’t want to end up in a situation where I’m limited to what I can do with the timing curve because of the quench distance.

If you added a full point of CR, and as much shorter as that cam is……..it should be a big difference.

I forget, did you do a cranking pressure test before tearing it apart?

The one I revamped years ago that was 7.7:1 pumped barely over 100psi.