After fooling with the axle for quite a while, I installed another circlip and had the same problem, so I took a look at the circlip under a magnifying glass and found marks that seemed to suggest that either there was no axle gear chamfer, or that the circlip wasn't centered:
I first re-greased the circlip and centered it in the shaft groove, carefully inserted the axle and tried again - no joy, so I pulled the case assembly, took a closer look and found the axle gears are indeed chamfered. Then, I tried installing the axle into the gear on the bench - no problem...... it went in easily so long as the angle was dead straight and if I used the outer axle end as a slide hammer:
And..... it came out easily with a good jerk - just like it should.
I never had this problem with the open OE differential - I suppose because the clearance is tighter with the Aussie gears. The issue is compounded by my Bilstein shocks which have a large diameter and make it difficult to get the right angle on the axle shaft for insertion. I'll have time to try it again on Thursday (my next day off) and I'll remove the shock. I'll bet it'll go in easily once the shock is out of the way so I can see the angle and get a better/straighter push on it.
I wasn't too thrilled about removing the case assembly again, but I found it much easier/faster to do the second time and used the opportunity to stake over the cross shaft lock pin hole, so all was not lost. <img src="/forums/images/graemlins/kewl.gif" alt="" />
Frank <img src="/forums/images/graemlins/cheers.gif" alt="" />