I do not understand all this rubber sleeve and o ring stuff, even in the military we had size specific tools.

Ive done near 250 small blocks with these and never had one single issue, even to reuse the cam bearings from the race motors in dirt track claimer builds.

I dont know how the Les tool works but ive caught 3 MP cam bearings that were sized wrong from the box with these as well by not fitting or fitting too loose.

Maybe I just know there might be a better way or ?