M1 15w50 is a good, and maybe the best option. I'm dreaming up another mega road trip and I might use it and then UOA test. The original owner of our 92 Lingenfelter Corvette used M1 15w50 in it since it was new.
Post pictures of your Lingenfelter Vette. Those things were a beast back when he was still alive.


As for oil, I would run 100% Mobil 1 without any Lucas.