With cork valve cover gaskets, I would just put the gasgacinch or Permatex "Aviation Form a Gasket" on the side that mates with the covers. Put a nice coating of axle grease or whatever all-purpose grease you have on the engine side of the gaskets. That way you won't have a hard time getting the covers off the next time, won't tear up the cork gaskets, and won't have to scrape off bits of cork with a safety razor and solvent that are glued to the engine. You will probably be able to use the gaskets again.
Regarding the paper oil sump gaskets, I put Aviation Form a Gasket on all sides of the two gaskets, let it dry a bit, and make sure all surfaces the gaskets are going to touch are smooth and clean. My experience has been that those paper gaskets can be pulled off intact pretty easily after the engine has gotten up to operating temperature multiple times. I still have to put some carb cleaner on a towel and clean the sump plate, sump, and strainer to remove old Permatex residue, though, but it's worth it. There are few things more embarrassing than when your sump leaks.