Kool Stop Tire Bead Jack.
I have been doing battle with a 19mm wire-bead Rubino since I got it about four months ago. I have probably pinched and killed a half-dozen tubes trying to mount the damned thing, and it's not like I'm bad at mounting tires. Plain truth is that it's a total b*tch of a tire to mount on a Mavic rim.
Two weeks ago, I was in my favorite LBS and I said, "Hey Karl, any tips on mounting troublesome, narrow-ass wire-bead tires?" He whips out the Kool Stop lever. The idea gestates. A week later I phone to see how much they cost and pick one up two days after that.
I get to the critical point of getting the last eight inches of bead over the edge of the rim and get out the new tire lever. The moment of truth....and it works perfectly. I will never even bother using another lever to mount tight-fit tires.