Thanks Ace!!! I'm glad to hear someone has attempted it and it worked successfully! Thanks for answering my question and for the advice!
I'll post some pictures after I cut it!
Regarding the AK47 expansion chamber, it leaves like an inch or so gap which is the problem... or so I've read. Apparently someone was talking about a 'vertical adapter' around here but I've yet to see any pictures. That real M16 mag looks sick though!