Newbie here, but on my recently acquired 42 Mercury, the PO had glued literally rope to the inner pillar and door ledge. I don't know what, if anything is or was supposed to be actually attached to the doors. I can look in the morning, but what Bubba did may not be correct.
From what I have researched, nothing in the serial number to assist with model type or paint codes. Supposed to be a patent plate on the firewall that I have not found, nor have I found the serial number on the frame rail. I did find mine on the trans inspection cover. But, again, it is just a serial number.