My levergun break-in and slick-up routine is to take off the wood, rinse out the grit and metal shavings with Ed's Red in a spray bottle, jack the lever hard about 300 times (thumb the hammer down each time, this part is important as it affects bolt and hammer nose wear patterns), then take it all apart and put a fine polish on all the shiny places you can see. The ejector on Marlins and the groove in the bolt that they ride in need special attention with tiny files and emery paper. Smear a tacky, synthetic grease lightly on all the contact points, swab a light coat of oil inside the magazine tube, and put blue Loc-Tite on all the screws when you put it back together, including the lever pivot screw (some people won't put threadlocker on that one because they want/need to remove the bolt for frequent cleanings, but the screw can back out and bugger the receiver threads before you know it during rapid-fire shooting).