Seeking opinions on how much to clean this. I was planning on removing the brown old grease/congealed oil and perhaps use some oil & bronze wool on the barrel and bolt handle. I could disassemble and use the ultrasonic cleaner on the action.

I don’t want to hurt any of the remaining finish, nor remove the age patina, just remove dirt and old oil

What would you do?

(I can repost this as a new thread if that better respects the intent of this particular post.)