Shuttle SFF and heat

I'm running a SN45G (see sig for specs..) and I'm loving it...
Just wanted to hear from those who are running AMD SFF boxes, how high of an OC have you guys gotten? What is the limits of the ICE HS cooling system?

I have my exhaust cut out and put a fan grill in place to help get the heat out, but I know it's toasty in my case...
Any suggestions on getting it cooler? (I've got a clearview coming, that should help a little...)