Acoustic Guitar live Mic/Pickup Q's

[Guitar-Sam]

OK guys,
I'm gonna be recording with my band in the fall and gotta scrap up as much cash as possible in the next two months.So in addition to a loan ,I'm whoring it out to every fillin gig,open mic hosting,band gig etc........to make a buck.
I'm not really a huge acoustic guitar tone freak.If it plays its usually good enough.
Anyway I'm gonna be hosting an acoustic open mic,to scrap up some extra money.
Now I've got a nice sounding beatup Fender acoustic but its not electric.I don't really have any extra money right now to sink into this,so my thoughts are.......................Shove a mic cord through this small hole broken in the guitars face and duct tape my sm-58 in the sound hole.
Will this get by or will it feedback like a bastard.

[Guitar-Sam]

Never mind I decided to just buy a cheap strat neck pickup and mount it in the sound hole.
I just don't want to sink money into this cause its just an open mic and I'm broke right now.