The bushings will do both. They will remove the endshake, but unfortunately in doing so they will shift the cylinder rearward and increase your constant cylinder gap. I've installed endshake bushings on three of my Smiths now with great results. If it were my gun, I would install .006" worth of bushings and test it out. Your endshake will be reduced to a more acceptable level, and your cylinder gap will be large but still workable.

Installing bushings is easy if you follow the steps correctly. Please ask if you need any help with that.

I have heard that there is another way to fix endshake, where the yoke is (stretched?) slightly. It seems this would remove endshake without increasing cylinder gap, but you would have to ask someone more knowledgeable than I on that one.