Did you ever figure out the dimensions that work for the GM/Chevy cargo vans? I see a couple posts about them in this thread but no conclusions. I have an Aluminess rear bumper with tire carrier being built and would like to do something with the space left by the spare tire. This looks like a perfect option!
If you have not figured out the Chevy dimensions yet, I can go pull my spare tire out and measure...thx!
2009 Chevy Express 1500 AWD SMB