Help installing aftermarket car stereo/deck

Hi y'all. Long time lurker, first time poster. Signed up specifically to get some help installing a car stereo. I'm a fairly technologically-inclined guy, so I figured replacing the stock stereo in my car wouldn't be much of a difficulty. WRONG.

I purchased this deck (thought not through Crutchfield) and figured it'd be an easy swap. I ripped apart the car to figure out I need an in-dash receiver kit, so I picked up this one. Then I go at it again, and find out I need a wiring harness to avoid chopping everything up, so I go out and get this one.

Now I've got everything I need to install this thing. I tried the other day, though, and couldn't get power to the unit. I'm 110% frustrated now and at a complete loss, so I need help. The harness kit came with a red 12V accessory wire (which I believe gives the unit its power) but I don't know how to hook it up or where. I read on various forums that it should go to the passenger side fuse box. The red wire came with a little fuse adapter thing so that you can plug it in with a fuse, so I stuck it in the radio fuse. No luck. I don't know if I hooked the wire up right at the harness, though, and it was cold as hell out, so I gave up, and now I'm here.

This process has totally sucked and any help would be amazing.

I've got a 2007 Pontiac G6. Sedan. Any other details I don't have right now, but can try and get later on.