I have never tried to do it because there is not much area on most stocks that is actually flat, because of the back and forth motion of the 1013 the design would be deeper at the crown of the curve than at the edges.
If you truly have a flat spot on your stock, you should be able to carve it.......but you'll have to come up with some sort of cradle to hold the stock still during the carving. Spent some time looking at my M1 Garand for an idea of what to suggest, didn't come up with much. I could carve easily on the bottom of the stock at the barrel end, and possibly do small sections on the rear portion length wise. Honestly I think Bob is correct, you would have a tough time getting a standard carving done on this.