For your SKS, you pretty much have to start out with blonde wood to get a blonde finish. It's hard to lighten up wood that is naturally dark. Hopefully your is blond now, pre-finish.
For the WASR, your wood will be like mine, probably light and looks like plywood.
I'd get some Formby's low gloss tung oil finish, sand the stocks smooth (maybe not so much on the SKS-you don't want to sand off the numbering or anything probably), and rub in about 8 - 10 coats. One coat per day max. You can cut the first few coats w/mineral spirits, then go straight on the last 5 or 6 coats. Don't overdo it, lots of thinner coats is way better than fewer thick coats.
Tru-oil will give you the same effect. Just remember to go easy and use thin coats, and let it dry between coats.