Play in centre shafts
 

This is doing my head in. I stripped my front centre drive shaft to clean and regrease the cv joint. When I put it back together through the gearbox case and screw the pinion gear on I can slide the whole thing forward and back through the case a good couple of mm. Surely there should be no play with this against the crown gear? I have read and re-read the instructions and can't see any shims. Anyone?

Problem solved. The shaft had the hpi alloy pin holders rather than the Xray plastic ones. The alloy ones don't rap around so there was a gap.