What a difference an inch makes.
Ummmmmm...... cooler heads might recall that Rick E covered this EXACT SAME THING in Mopar Action a couple issues back.
I don't recall the factory solution precisely, but seem to recall that it wasn't too far off from what the OP did. And I was kinda surprised by that and thought it seemed kinda low brow but it must've worked.
One of y'all that's wound so tight about this can look it up and see who wins. Imma go look at some Croation AK mags I just bought. They're oily and they smell bad. They're pretty neat.