Not sure you really want to take these guns as a hood ornament.
1) highly illegal and would restrict the use of the HM on most planets
2) held together with duct tape and spot welding. You know what happens to both when they get hot.
3) you would have to rewire the controls completely
4) we are talking redneck ugly.
5) did I mention the duct tape?
as to cal, these rules really aren't set up for different cal per damage.
Odyson -

I can not believe you actually didn't try to perform some sort of first aid on Winnie. Not even a bandage or something! OMG! Pressure on the Wound! Anything!
I forbid you to change it because it is so funny considering what will happen next.