Heres my setup from tank to carb...
1991 Camaro

Stock intank fuel pump
Stock 5/8" line(I think?)
Stock TBI fuel filter
Carter 120gph fuel pump
6AN fuel line to Holley regulator set at 7psi
8AN fuel log
Holley 770 street avenger

Now my wonders are...
I'm assuming the carter pump will have problems pulling through both the TBI fuel filter and intank pump in higher gears/rpm. If I were to setup a switch to turn on the stock intank pump would that be ok or will it cause problems with the mechanical pump? I've run the car around the city with no problems of fuel supply but havn't had any high speed WOT passes with it yet. I guess I'll just have to tape my FPG to the window to really find out but what is everyones experience when trying to run a mechanical pump through an EFI(TBI) fuel filter and intank pump?

This setup has to feed a ~450hp 406.