T02 = TB02R identical in all ways
TB02, TB02R, EvoIII Surikarn identical except Diff Joint
Standard diff joint T51042
short side has a moulded nut retainer, and that is why the diff spring can not go on the nut side with this diff joint.
Nut on short side (it fits in the mould)
Spring, thrust bearing on screw side.
EvoIII, EvoIV, EvoIVms T50992
uses a seperate nut retainer (A5 part evoIII surikarn, L10 part EvoIV, also same as TA05)
Long diff joint - spring with nut & retainer
Short diff joint - thrust bearing and screw.
One other difference I have found is the ring gear and bevel.
T50987 TB02, TB02R, F201, EvoIII surikarn
T51110 EvoIV and EvoIVms
I personally have not compared these items (but I will very soon and update all)
I use tamiyausa.com parts support system to compare items and research compatability. Another good web reference I use is tamiyaclub.com
(and of course rctech)
tamiyausa parts support http://www.tamiyausa.com/product/rcpss.php
tamiya club www.tamiyaclub.com
just wish i could order in a dose of consistancy for my driving