Here's a place to start:

http://www.marlinowners.com/forum/do-yourself-gunsmithing/

It's a very good forum for Marlin things. And if you join and ask for help you'll likely get much info.

Since it's a new Marlin you might contact Marlin for warranty work.
This thread may be useful also:

http://www.marlinowners.com/forum/marlin-rant-forum/

Retired cat herder.