I went ahead and disassembled it.
To see the below names and numbers the gun has to be completely disassembled.
147 on bottom of trigger guard
82 on bottom of barrel tang
82 hand written on front end of stock in barrel bed
SPAIN on back side of lock plate at bottom, below main spring
82 on trigger frame
82 on side of trigger
I don't think it has ever been fired.
I did go ahead and clean and lube it even though there was no rust. There was plenty of dust. I used bore butter to lube all metal parts, inside and out, then wiped it very good inside and out.
With my lil ole cheap caliper the bore measured a very close 7/16. 7/16 = .4375. So I'd say y'all are correct in saying it is .45 cal. I have some .440 balls.
What holds the ram rod in?