Congrats on your purchase, if you are going to mount the T28 from the GTiR I will say to look for the GTiR manifold, I just install a T28 from a GTiR and indeed will need a different mounting.The easiest way is getting the GTiR manifold or do some modification to your own.
Yeah, I think the reason they hi-flowed was it was an easy bolt on.
Now I have too many cars though. I have 4 currently. A VT Commodore that I have been meaning to get ready for sale for the last 6 months (LS1 V8 Executive), a Hyundai Lantra which I use for work (I do about 25,000kms a year in my job), my project pintara and now the bluebird attessa. Like to keep the bluebird for a while and definitely don't want to sell my project car just due to the cost and time I've spent...........especially as the pintara is almost ready to get running again and a tune!
There are some good buys out there at the moment. Heaps of 4wd turbos for under $7,000, new v8's. 15 years ago you'd be dreaming to get the type of powerful performance cars on the market.