I cleaned it with Howard's feed N wax, but it looks just about like it did before, minus some grunge.
No stripper, oven cleaner, water, soap, steel wool, plastic brushes or sandpaper got anywhere near it.
It's stained beech with a walnut handguard.
I use "Howard's Feed-N-Wax".
It's made of bee's wax, orange oil and a little petro solvent.
Very mild but works well.
Most important is that it will not damage the original finish in any way.
Several treatments repeated over several weeks for grungy stocks.