Oyeboteb and opoefc , I’m disassembling it because
1. I want to give it a good cleaning
2. I intend to fire it with blackpowder loads and want to make sure I’ll be able to disassemble it afterwards!

All, good suggestions on the Kroil (never heard of that) and the “Dean” method! I actually considered something like that but hoped I could get a hold of an alternate longer screw with identical Shaft and thread dimensions!