I built my official Durango 210 gear diff today and I must say with two open ends it's much easier fitting the cir-clips compared to the 410 diff. Also the crown gears slotted neatly onto the shafts without requiring a hammer
The tolerances look good and it meshed well in the gearbox. I followed the ball diff build and put two bronze shims either side of the outdrives, but I think this is just a tad tight for the gear diff - probably one each side is better.
It could be my imagination, but I felt the standard 'O' rings that came with the set seemed to bed a little tighter into the recess compared to the 410 diff. Therefore, rather than use the other alternatives, I've fitted these and I'll be interested to see if they will leak.
Following an earlier tip from HULK (Craig) I've always built my 410 diffs smearing Marine grease on the 'O' ring and I've never had a problem with oil leakage so I did the same on this build.
I can't wait to try it at Formby this weekend (medium grip carpet).