I guess that's why you call yourself overthehill. Ha,....anyway, yep, I believe those IT200's and the 175's etc.. are really good bikes. Just had a post up on a Facebook yz125g forum I belong to, and the guy posted up a pic of Himself racing mx on his IT with one of GMC's cone pipes. Said they work great.
Geoff is interested in the concept of a 125G race pipe, so fingers crossed it works out..