So I guess I'll need to get the engine & gearbox back out to get at the bolts between the sump and gearbox
I've only drilled one hole into the inlet manifold I made which I tapped for the temp gauge sender. This doesn't appear to be leaking. I also took the core plug out at the back of the head at the right side as you look at the engine from the front which is where I mounted the FWD thermostat. Again this doesn't appear to be leaking either.