Any of the liquid strippers should work. All you want to do is remove three painted numbers and acetone should do that too. A real cloth and lots of acetone, just wipe the affected area and keep changing the cloth to keep the paint from streaking into the rest of the area. Providing the stock isn't too dark with crap it should do the job without changing anything else. There are many products to clean and restore the walnut finish. BLOicon is but one. Cheesecloth? Sure.