rear main leak

You can and should be running something other than just a PCV valve.

Bill Jenkins was running both in the early 1970’s.

It’s how I do my engine. ME Wagner PCV valve and pan evacs.

I run mufflers.

You need something for WOT.

I’d make sure to use an air/oil separator between the PCV valve and the carb.
Any chance you could napkin sketch how you have the plumbing for running both types of systems? I know how to do them separately, but curious how that plumbing works when combined. Breathers on one side of the engine, pcv on the other? Or are you venting on the valley pan or somewhere else? Do the little valves on the pan evac lines keep them from being open when not at wot? I could also pop a connection point into my fuel pump block off plate if necessary.