Thank you for all of your input.
The more the merrier.
I am not going to sand it.
If the substance will not come off with chemicals I will not sand it and scratch it up.
From the photos and what the seller told me, I do not think the same substance is on the stock.
I am hoping to leave the stock alone.
I think here less will be more.
Like Patrick said, start with the least powerful chemical and move up gradually IF necessary.
I also do not think the gun is shiny under the yellow substance.
I think that is just the way it looks in the photos.
I probably will not get it until this Friday but I will definitely keep you all posted.
I will likely be seeking opinions once I have done my best cleaning job.
BTW, it is nice to have everyone rooting for me.
I am sure I will get this rifle cleaned up.
I am very determined.
Frankly, I hated to see a gun with all early parts which are matching and correct be left in such a poor state.
I am still hoping to make it collectible.