A few things I've learned about the A/C belt and pulley; hope this helps.

Having the right tools (below, not expensive) turns this from a knuckle-busting frustration into a 30-minute job.

* If you're getting a squeal from your belts when you start the engine, don't just assume it's the easier-to-change serpentine belt and tensioner. Don't ask how I know :-)
* An easy test for which belt is squealing: while it's squealing, turn off the A/C with the snowflake climate control button. If the squealing stops, it's your A/C belt.
* Both torx bolts are T45, but a T40 is a lot easier to fit on #2 - especially if you use a 1/4" T40 socket.
* I loosened #1 a half turn with a 1/2" drive T45 socket from above
* I loosened #2 from below enough to slip the belt off the tensioner. Had to loosen it a lot further to get the new belt to fit. Used that 1/4" T40 bit and a 9" 1/4" wobble extension from Harbor Freight. Turn counter clockwise to loosen, just like a ordinary bolt. I threaded the bit and extension through a hole in the large shiny black subframe, just forward of the engine.
* Taking off the A/C belt requires pulling the serpentine belt from the crankshaft pulley; you don't have to take it all the way off all the pulleys. However, if you're going to replace the A/C belt, you might as well replace the serpentine belt, too. The tensioner is a T60 Torx