The air velocity in the intake runners/cylinder ports will be much more important than that at the TB. Use the larger TB and see if you get gains. I suspect you will see some, though whether or not it will be enough to "feel", I don't know.

Also, you didn't mention anything about the TPS. Did you use the Mustang unit, or did the stock TPS from your SVT bolt right up?

"When I take action, I'm not going to fire a $2 million missile at a $10 empty tent and hit a camel in the butt. It's going to be decisive." - President George W. Bush

95 Contour SE ATX V6
"Cracked" Secondaries
DMD Installed
SVT Brakes