How long is long enough when Baking your own grains?

OK, so I've decided to roast some of my own grains. It says to let it sit for a week or more. I'm sure the more you roast it the longer it should sit to get rid of the bad flavors but if you were going to go to a lighter roast, lighter than amber in color for instance, what would the wait be? Was planning on doing up 2lbs 2row to a crystal 30ish color(I know it won't be like crystal because the starches havn't been converted and all). About how long should I wait to brew If I baked it up tonight? I know if I was to do up some chocolate in color grains I'd bake it up 2-3 weeks in advance. In a well vented area mabye with a fan pointing on the grains blowing full blast with a false bottom could I possibly cheat the wait and brew tomorrow or am I just asking for disaster?

check out radical brewing by randy mosher. it has some good info on this procedure, but as an fyi for you, a lot of color can be hidden in the grains, even if they don't look that dark. Next time you are at the lhbs put some crystal 20 and some crystal 60 and some crystal 120 on a table next to each other and look at the color gradient so you know what you are approximating.