BD 14 & BD 15 for yer cams, rs500 inlet and throttle body.
8 greens at least, get yer head ported more.

I dont know much about the gt turbo's (prefer to stick with T4)
What exhast manifold does it sit on..... if ya aint already got one get
a 2wd manifold

You haven't said wot compression you've got..... get some 7.2:1 cosworth pistons.

That little lot should see over 500bhp