Scott is totally correct in his analysis of your problem!!! I ran into the same problem with my T5 install....and cured the problem by slightly extending the splines.
I've documented the process with pictures and some instructions on page 5 of my Webshots "Shoebox". The key to getting the clutch to function properly, is to USE THE DISC on the massaged spline to make SURE it slides 3/16 to 1/4" past the end of the factory splines. If you don't slide on the disc and make sure it will slide past you may (or may not) solve your clutch drag problem. I hope this helps you solve your problem.
