Sorry for the stupid newbie input, but I'm assuming you guys are going to Ouray for GOX3. I've been going to that area every summer for 14 years. Ian is right. In July, very few of the passes will be open. You won't be able to run Imogene, Black Bear, Poughkeepsie or probably even most of the Alpine Loop. I realize that for a lot of people with children in school (or those that are attending themselves) Labor Day isn't the optimal time for you, but any other time of the year in that part of the country, the trails are pretty much closed if you want to do the entire trail.

Two cents,
Sean