i know and understand what's vector03's problem.
can be due to a few reasons that there's 'no room' for shimming:
1. 'sometimes' it's the crank shaft that's 'abit' too short
2. the 'cone' is not letting the flywheel sit close enough to the engine front bearing.
3. the thrust bearing retainer/holder is too short.
if you cant find a cone that lets you fit the flywheel closer to the engine; you could try to find a thrust bearing holder that's longer.