To be honest, if I were to pick a W-body to mod it'd be the 97-03, 00-05 Impala, 00-05 Monte breed (and I did). They're all pretty much the same. 04+ GPs and 06+ Impalas/Montes just make make it difficult. Not impossible, nor a waste of time, but more difficult.
I can understand that part of what he was trying to say, but the rest of what he was trying to say got lost in a jumble...