I have a very similar M92. I don't think your fine rifle needs "restoration". All it requires is removal of any rust by scraping with a flattened brass cartridge case and applying a good gun oil afterwards. The stock and hand guard needs a good lemon oil furniture polish applied vigorously with a soft cloth to remove accumulated dirt /grime. These procedures will not change the original condition. If you start adding finish to the wood, you have changed it.
Restoration means different things to different people. To me, restoration is not the same thing as 'refinishing'. If done properly refinishing can be part of a restoration, done improperly it can make a decent restoration impossible.
As far as cleaning rust, I've been using 'Frontier Big 45' for years, and am a big fan. It does a great job of removing rust (and other 'hard to remove grime' from metal) and have never had it affect any metal finish.
If the wood of needs cleaning, I first see if I can get the dirt off with elbow grease and the oil I plan on using on the wood. You might be surprised how good oil (animal or vegetable based) is at lifting dirt. If that doesn't do a sufficient job, I use dilute Murphy's Oil Soap to clean it. Then the oil goes on. The oil I use on the stock is what was used (to the best of my knowledge) when the firearm was originally made - in this case raw linseed oil.
