I have a right angle air drill if you have a compressor. It's only a 3/8" chuck though, so getting a 9/16 drill with a 3/8 shank might be a challenge, unless it's a step.

Or if you have a compressor I have a right angle die grinder and burrs to make any hole or shape you want!

Let me know if any of these help. I'm heading out of town early Thursday morning.