I had a worry that the Skyline gearbox would need 3.9 drop gears to suit the 3.9 Supra diff but it turns out the gearbox is 1:1 so it is better to change the front diff to a Quaife 3.9 Atb with strenghtened casing, this allows the box to stay as it is and I gain a front ATB with stronger case over the standard open diff. The down side is that the crown wheel and pinion are smalled on the 3.9 than the 3.6 std so COULD be the weak link. As the car is a road car for 95% of the time and I have never taken a car on a drag strip and have a lot of mechanical sympathy (and I am an old bugger at 41) I doubt I will be over stressing it.

ALSO with the Skyline box and ETS pro controller I can dial the torque split back to more rwd bias if I do want to get silly with launching etc.