Sheared water bottle bolt
Not really sure if this is the right forum for this question. It is somewhat related to the frame...
The bike I recently got came with cheap aluminum bottle cage bolts. While installing a plastic pump bracket, I sheared off one of the bolt heads (didn't torque it down tight, I'm guessing the bolt was cracked). Now there is about 2 mm of bolt sticking out of the threaded boss. I tried some pliers, but there's not enough to grab on to, and what it can grip deforms and starts to round it off.
So how do I remove it? Difficulty: it's the bottom-most mount on the seat tube. There's no way to get a drill in there head-on since the down tube is in the way.
Would this be a job for the LBS? Or am I hosed?