PS,
Here is the GTX3076R and 60-1 compressor maps for reference.
The GT is happiest at about 1 bar and at about 375chp. The 60-1 at about .6 bar and 350chp.
For a street car you kind of want your best turbo efficiency at about your peak torque point. Is so that should make the 60-1 in the range of a good 400chp low boost turbo.
Add about 10% for the Turbonetics 62-1. If you have there hi-flow small frame option take about 10% off each.
Again, not an expert and there may be better options from others.
