For what it's worth, you should keep an eye on that JB weld. Don't get me wrong, I love the stuff. It's pretty handy and I use it everywhere I can, but I would never use it to build up a contact wear surface. Eventually it will likely break off that trigger and end up lodged in the action somewhere in pieces. It's a bit of a hack shortcut to achieve the results of the proper grub screw technique. I'm not saying it won't hold, it might. I have read about other people doing it, but who knows how long theirs will hold.
I just often wonder why so many "fixes" are done with JB weld/duct tape/bailing wire etc...
And as far as I know the new marlins are the exact same.