Any Subaru rear diff & output shaft experts?

[itiejim]

I am just completing the fitment of a Subaru rear diff in my Triumph Spitfire. The diff is from a Classic Impreza and has a viscous LSD and, I believe a 4.11:1 ratio. I bought the diff from a chap who had numerous diffs and output shafts. He specifically pointed out that I needed certain output shafts with longer splines in order to engage with the viscous element in the centre of the diff and went through his pile to find the "correct" ones.

I have now virtually finished the project and am struggling to get the shafts to locate in the diff. I did try one on the bench and it went in fine, however, when I try to put both in putting pressure on one forces the other side out! I am therefore beginning to suspect that only one of the shafts should have the longer splined end. Can anyone confirm and, if so, identify which shaft I need and whether they are handed?

[itiejim]

Thanks for the help Stevie. I'll get my shafts out again and contact Matt to see which ones I need.

[itiejim]

As an update, I found and spoke to a local Impreza breaker, SMR Auto Services, who told me I needed one long shaft and one short one instead of my two long ones. He provided one for £15 and all is now good!