OK...
I will start to give you guys the 1st part of the Puzzle for making the Durango Dex410 Gear Diffs work with the TRF 502x... the parts list... it's going to cost a little bit but it will be worth it not having to deal with the TRF502x ball diff maintenance

Anyways... on with the parts list...
Durango DEX410Parts
TD210001 Gear Differential Set x2
TD310005 17T Bevel Gear x2
TD310116 Driveshaft Gear Input (2.0mm) x1
TD310145 42T Light Weight Machined Differential Ring Gear x2 (
Optional)
TD310290 Light Weight Molded Cross Shaft/Gear Set x2 (
Optional)
MIP Parts
13126 Center Input Hub x1 (
or x2 depending on shimming)
13133 Center Drive Shaft Front 89mm x1
13141 Center Drive Shaft Rear 69mm x1
13122 #1 Pins & Screws x1
13121 #1 Orange "PUCKS" x1
So this is
Part 1 of 4.. and I will have Pictures to follow in the upcoming weeks on what areas need to be modified in the gear box housing to make the diff fit.. most of everything is drop in and the drive shafts are Lightweight alloy so they will be comparable to the Alloy TAMIYA ones.. if not lighter...
One last thing.... we might be able to make the Durango DEX410v4 Two Way Slipper fit as well

more to follow...