how did the flywheel look when you seen it? if it had dark spots on it then those can cause it to slip and also if the surface is not flat it wont grab correctly. check other things before you take off the tranny again. pedal adjustment(adjusting the clevis), bleed the clutch line, check the slave. but this sounds like a pedal adjustment problem. but not resurfacing your flywheel can cause this problem why didnt you resurface it how did it look? heres a pic of what to adjust.
