Mark,
We're pretty much in the same boat.
I have already ordered my turbo kit, but I am waiting for the rest of the bits (fuel kit, aem) before I do anything.
I am also changing to a TT6 first as the auto is going to be too much hassle.
Leon @ JPS knows a lot about the auto boxes, your going to need to speak with someone about this.
I know you do a lot of drag racing so he's your man - the auto wont last 5 minutes doing drag starts with a decent powered T66 on the motor.
I am going SP63. 81 A/R, HKS Ex 264 Cam, Aem, Blitz 850cc fuel rail + all associated bits. My power goal is 500rwhp ish, and I will be using it day in, day out.
Gaz.