I just found an old Marlin Model 99 in my father in laws barn. It was his oldest brothers gun, and he just passed away a couple of months ago. So, I was thinking of completely refinishing it up for him as a Christmas present, and I could use all the help I can get. First off I am trying to find out the history of it. I cannot find anywhere to figure out the year it was made. It has no serial numbers, and all I can find are the numbers 400-10A G1, there were located inside the chamber when I took out the whole action assembly. It is in really rough condition. Next problem is that it took me 3 hours just to clear the bugs and mud out of the barrel. For the most part the rifling and bore look great considering the condition it is in, but the first 2 - 3 inches from the chamber show a rust/pitting ring where there mud was located. Any suggestions on fixing that? Thanks for any help, and I am sure I will be asking more questions as my progress gets further into this project. Thanks again.