If I had it to do over I would have stayed with my Plog, stock rear mani and Hogan DP.
Anything other than a stock TB will likely not be beneficial until you are running a 3.0 pulley or smaller. One of the big tuners that holds tuning classes across the US and is currently a GM OEM caibration engineer had some interesting things to say about porting stock TB and or installing a larger TB.