im trying to figure out this center intake mod needed for stage 2 and kibbles..Ive measured over and over and seem to be getting 10.4s to 10.5s clearance between the valve seal and the retainer. the lift is 10.65 so i know i need to mod it. my question is whats the best way to go about it. From what im reading, i hear people saying to take off the same amount off the bottom of the seal also.. ??? I thought that the guide would have to be removed from the head and it taken off the bottom (or top,whatever way you want to look at it) if taken off the stem end, the groove will still be in the same place. I dont understand how that will alow the seal to sit lower. maybe im over thinking it but i dont see that working. if taken off the seal end of the guide, will the seal actually still be in the groove and stay in place? Is there enough play in the groove to allow it to move down? if so how do you take 1mm off evenly? Im trying not to take it to the shop to have this done. but its looking like i might have to. Still, i can see them telling me i need a new valve guide to mod befor installing it.. If any of you guys have done this yourselves or know exactly how someone else did please help.. this is driving me nutts !!!!!!