That is how it is setup exactly and how it works. A lot of forced induction cars after market run staged fuel pumps with a hobb switch for boost. I didn't invent that design. I just utilized it. I see no reason why a Z with dual pumps can just have one pump run off the stock fuel pump controller. The second pump is not needed until in higher boost. I believe my Z is the first Z32 to use dual walbro pumps. I even posted pictures of my dual pump set up. Anything else you want to know ?
"Yes, I know more then JWT. Someone has to be the top dog, and it just so happens it's me." Nixit