I'm not far from you Andrew, Warwick, 4370. I do want to use an auto for circuit racing, used a shift kitted GM 4L80E behind the LS3 controlled by a Powertrain Control Solutions TCU and it shifted great, only problem was no engine braking. Probably best to move this conversation to pm but for anyone else interested here a couple of questions about your complete set up. I assume that the TCU will not be user tuneable so how do you supply it pretuned? I'm not fussy but do require strong engine braking and fast snappy shifts. As for the ECU, what about user tuning if, say, the cams are upgraded? There is a good dyno tuner here. Thanks and cheers, Richard.