Did you ever end up going farther with this project?? I'm very interested as there are no Solstice AR5s nearby, yet plenty of Colorado ones.So upon further research it looks like there are 2 types of AR5 (MA5 really) in the colorados/canyons and hummers. It depends on whether it is 4x4 or 4x2. We want the 4x2 version. That looks to mount up like the solstice/sky AR5.
What I have been able to find, and kind of just deductively say this, that 2004-2012 Colorados as long as they are 4x2 trucks and not V8, they use the same transmission.
I say that because when I looked up the part number for the manual trans for a 2005, found this:
This says this transmission fits a 2004-12 Colorado and Canyon. I assume that any year in there with the 1jz bell housing, with the 5mm shim I posted above, and the custom shifter, should work in the IS.2004-2012 GM part # 24284716 - Transmission Assembly-Manwww.gmpartsdirect.com
I plan on trying to go to get that transmission at my local yard tomorrow morning, if its not pouring rain. I'll let you know what I find. I believe its a 2005 truck 4x2 that it is from, from what I can find on car-part.com