For the sump gasket on my twin cam, if it is a cork type, I fit it using gasket adhesive (eg Permatex Aviation), brush on and allowed to cure with light pressure from the sump for 12 hours before correct torque on the sump bolts. This will stop the gasket extruding when the bolts are torqued. Also easy to clean off with solvent compared to RTV on engine dis-assembly. Also ensure the sump fitting flange is flat prior to fitting - it can get distorted at the bolt holes from previous over torquing.