Wow Josh. Your Z car is my favorite car that Nissan / Datsun ever built...
Sounds like you lost oil pressure...
As a former automotive engine machinist, I would also pull the pistons and check the wrist pins. I have seen them replicate the same noises you described. Then disassemble and check out the clearances inside the oil pump on the rotors and housing, making sure that the oil pump drive didn't fail or the oil pump relief spring didn't stick...
If the engine ate a bearing then its a good idea to totally disassemble the engine and clean everything, since fine metal particles have a way of getting everywhere ...
another spot to check is the line bore on the main journals, especially if you spun a main bearing...but rod bearings are more likely to spin than a main is. If you spun a rod bearing then definitely install new bolts and then get the rod re-sized . Any competent machine shop can do this.
I really like using Bare metal foil. I have a B-17 in my work pile that has been started using it. Your '29 looks great.
Please post some photos of the Wildcat when you can, and enjoy the Holiday weekend bud.