It would be great if there were a sticky on how to get your Montana in shape!
Well, FWIW, here's my ritual:
First:
I buy one that has the barrel centered in the barrel channel, is fully floated, and has a good grind on the recoil pad. If both bolt lugs are making contact in the recesses, so much the better. Not looking for perfection, just close enough on all counts. Frankly, this generally precludes buying sight un-seen.
All of this is my method for any new rifle:
a). Bed entire receiver and under barrel shank. This may or may not help but it will never hurt.
b). De-Grease bolt and trigger. Re-Oil.
c). Adjust trigger to 2.5 - 2.75 lbs (a good trigger is critical, especially on a rifle as light as the MT).
d). With fine rat-tail file, break top of feedramp.
e). 600-grit emery underside of feed rails and feedramp.
f). Snug, Loctite and nail-polish bolt shroud/firing pin set-screw
g). Remove Sling Swivel Studs, dab JB Weld on each Stud Swivel Shank, and re-set in stock.
g). Eesox all metal below stock surface.
Also:
I JB Weld scope bases to the receiver top. I generally lap/de-burr rings, but the Kimber is essentiall straight/flat enough it's something that can be skipped.
Mount the scope in rubber cement.
Blue-Loctite Scope Ring Screws.
Additional thoughts:
It's important to know a rifle as light as the Kimber MT is finicky when it comes to loads. Not only does it require nearly perfect bench technique, but its light barrel (and light overall weight) preclude it from shooting everything with boring regularity.
Since 2004 I've loaded and shot for 13 Montana's (have owned 14)... every one would shoot sub moa with something, but if you're determined/set on one bullet weight or particular bullet or powder, you'll likely be disappointed.
BUT, if you're more flexible and are willing to experiment (fore-going a lot of per-determined expectations/conditions), you'll find something that will shoot in the 3/4" range (or less)... if you can shoot.
The light Kimber MT will humble one at the bench...
