you guys hang out so much your starting to look a like

but red hair err...:wink:
It's actually red scalp....I gave up on hair growth 100%
Back onto our friends subject.
Good cork gaskets will work fine on the valve covers.
Assuming the valve cover gaskets are leaking, you need to make sure the sealing ridge on your heads are clean, and also make sure the sealing lip on the valve covers are clean.
Use a little black oil resistant RTV on the valve cover lip, mount the cork gasket to it, let it set, then mount the valve cover and be sure to put even torque on the 4 valve cover bolts.
Rear main seal....good luck...you'll be able to slow it down...maybe even stop it temporarily...., but if your running any boost, it will start leaking again sooner or later as the crank case pressure builds from blow by and forces oil past the rear main seal.
The oil pans tend to also leak from around the pan screws. they let a little oil seep through. Using some good RTV sealer on the under side of the screw heads is one way to try and combat this.
good even torque on all the pan screws, and don't over tighten or you damage the gasket.