Im wanting to upgrade my current TR3650 5 speed to the T56 6 speed. Also change the diff to 3.73. from 3.46. Has anyone made these changes?

Let me know how you go if you do get it done, as I'm trying to do the exact same in my BA XR8, a T56 with 3.7 diff.

A few blokes ive spoken to say to put the 4.11 gears in. The revs should go up 300? in top 5th gear, which is the same ratio as 6th in the T56 im told? Think I 'll go that way (4.11) then box later?
Also heard oil quality is important for the box so im changing that too. There"s more, need a tune
for cruise control to work with changed diff gears and if you fit T56 you have to pick up rev light off box.

I've gone from the TR3650 with 3.23 single spinner to T56 with 4.11, well worth it 100km sits on about 2100 revs and heaps better off the line