Car won’t start after alarm install?

Hello all, I recently had an alarm installed last Monday by a local shop and I installed a headunit into the car myself (Eclipse 3402). Ever since they've been installed something keeps draining my battery overnight. I've disconnected the headunit and still have the same problem so I don't think it has to do with my wiring. I have a brand new battery on the car and had that and the alternator checked out at autozone and they seem to be working fine.

I ended up taking the car back to the shop and had them take a look at it. They measured the draw from the battery with the car off and from what they say it's taking a small amount of power, nothing that would kill the battery at the least. I'm running out of ideas and things to try here, any help would be appreciated! Thanks

Forgot to mention car is '01 Honda Civic DX, alarm is an Autopage RS-855.

Would the fuses be close the brain? I've pulled power (the 20pin connectors) to the brain already and the problem is still there.

Yup it was the alarm system, I took it back to the shop and had a different installer take a look at the alarm, he pretty much had to rewire the entire thing. Just a bunch of things that were screwed up with the install, the guy was telling me something about how the doors were hooked up to the dome light or something like that and some other stuff.