When I purchased my SKS it was literally dripping goop. Here's what I did:
-complete tear down, cleaned all metal parts with brake clean and then applied a light coat of transmission oil, except the trigger group, used Remington dry lube
-put the wood pieces in the garage and sat with wifey's blow dryer, heated them, used a cloth damp with varsol, wiped them, heated, wiped and repeated process for about 4 hours--keep beer nearby. You know you are done when no more cosmo comes out of the wood when heating it.
-rubbed all wood parts with full strength liquid Murphy's Oil soap, let dry
--touched up scratches with wax furniture repair pencils from home depot
-applied several coats, for first coat heating wood parts with blow dryer, Howard's Feed and Wax. Subsequent coats applied every couple of hours with warm wax but room temperature wood
I now have an sks with a beautiful, hard finish. PM me if you need any photos or tips