Colt 1911 assembly-whats the trick?

[Jagman]

To insert the slide stop without scratching the frame or the slide.
I have a 70 series (my first purchase 25 years ago) that has a semi circle scratch from inserting the slide stop, but this is a shooter so Im not too bothered about it, but I have 2 other 1911's that I dont want to scratch, I always use extreme care when I dismantle my unmarred pistols and employ my wife to depress the plunger so I can insert the slide stop straight in without having to pivot it.
There has to be a better way?
Jagman.

[Optimus Prime]

I always put the slide stop in mine before I even put the spring back in. But I've got a full length guide rod, I don't know if that makes a difference.

[Rexican]

I also put the slide stop in first, and the only trick I know of is using one of these. King's bushing wrench: mine's seen a bit of use