Still C85 Nose Leak

Previously this list advised a split seal is used on my flanged crank C85
and I then verified my case vent, hoses and air/oil separator system were
not blocked.

Since rather than pulling that spinner, prop, nosecone and cowl baffling to
install a new crank seal, would like to ensure I'm not missing something
easier. Recently a guy mentioned putting a gauge on the vent to determine
if case pressurized??

The engine compression has stayed at 79/80 hot for the last few years with
my oil usage not changing although the air/oil separator system may have
had a partial blockage for 6 months or so until I recently replaced the
hoses and cleaned it.

My question is: Once that front split seal leaks, will it ever stop leaking
and is there any test/check to ensure the case is not being over pressurized
to the point that a new seal would just start leaking??? (What causes over
pressurization?)

Thanks, Dick