Originally Posted by stevieturbo

Gear can be calculated from vehicle/driven speed and rpm, both of which the ecu should know. If your T56 already has a speed sender on the box, then that will make that aspect easy without the need to touch the ABS. Or it'd also be easy to add one to the propshaft or whatever.

And easiest and quickest way to reduce power would be via ignition timing. Of course yes you could also do DBW, but it really wouldnt be necessary.