You will need some clearance between the PP levers and the TO bearing because the levers will move some at RPM due to the counter weight effect. I think somewhere around .250". The thickness of your disc will affect the lever height so you need to make sure all that is set up right. Do you have a block saver plate on it now? Some guys will double up on the plate to increase clearance. You might also be able to make a spacer plate to use between the transmission and the bellhousing. Make sure you have enough input shaft, to reach the pilot bearing and enough dowell pin and bearing retainer register to keep the transmission centered when doing any spacing. You might just need a different TO bearing. You might try the UMTR forum here
www.umtrnorth.com/forums to see if someone else has a similar set up. You have to be a logged in member to view/post but you will find more stick car info there than anywhere else on the web. Good luck.