well, if you go for a different rail, make sure to get the mini cp rail, and not the larger standard sized rail. the standard rail is much larger than
Use the CP mini and no rail. You can have Luke dovetail the frame. Would make for a nice small and clean setup.
It's not technically impossible to do a bottom feed mag on an automag.
Someone on here did a custom pump frame that was moved back behing the breech.