I am assuming you want to put the ammonia in there to remove the copper fouling. I don't know if that will work very well in the presence of all that oil (ATF). And that sounds like a LOT of ammonia (25%). Anything with a lot of ammonia will cut right through linseed finish to bare wood in seconds (like 3 seconds, not 30). Sweet's 7.62 ammonia laden solvent cautions against leaving it in more than 15 mins. I hear it may cause corrosion if left in for a long time (don't know how long is long) I do use straight ammonia to strip gunky stocks and that thin hardened cosmo that resists everything else, takes seconds to come off and after water rinsing I have had no problems.