I have a 1972 Super Beetle and im leaking oil from the main seal, at least I think its coming from there. The leaks are coming from under both sides of the engine case. How difficult is it to fix the main seal? Can a faulty oil cooler seal cause the muffler to spit oil? What should I do? I appreciate any advice.

If it is the main seal it will be coming out of the engine to tranny seam. If it is running down on both sides of the case aft of the mount flange it would be the oil cooler leaking. Oil cooler seal would not cause the muffler to spit, the cooler seals are external of the engine.
Clark

If there are leaks on the main and the thrust, the seals are probably worn which may be a sign that you need an engine rebuild

it could be push rod tubes.