This should be an interesting nightmare. I can't imagine what you are going to do for bulkhead clearance. Side clearance should also be interesting, the turbo side might be alright but the intake side will be an interesting challange due to the position of the starter. I won't even mention intercooler piping.
What are you going to do about the electronics?, I'm guessing megasquirt.
If you can shoehorn it in there it it should make for an interesting ride. the last 2jzgte with megasquirt I saw on the dyno put out over 500rwh.