Baker Model A 12 ga double

I have a Baker Model A 12 Ga circa 1903. I shoot it regularly, but the other day I noticed the firing pin on the right barrel was not retracting and I had to push it in with a screw driver blade to open the gun. It still cocks and shoots both barrels, but I need an exploded view to figure out how to disassemble the action and what part is broken. Anyone seen an exploded view for this shotgun?-thanks, matt scoble