Vacuum to EGR (solenoid, delay valve,etc)?

[PHOENIX]

I have a new EGR and it is the correct one.
It is working properly, but it is working too early.
I have it hooked to the port specified by Edelbrock on my Edelbrock Q-Jet 1904 carb.
I have stumble off idle and purchased and install vacuum delay valve from GM as noted in Edelbrocks instructions.
The valve helped, but the stumble is still there.
The GM dealers tell me the valve is for automatic transmissions and they dont understand why Edelbrock would say to use it with the EGR. This doesnt matter much, because I catch the dealers being wrong about something every so often.
Checker and Autozone say that they show nothing in their computer for this and cant help me unless I know a part number or something.

I NEED SOMETHING TO INSTALL BETWEEN THE THERMAL VACUUM SWITCH AND THE EGR VALVE. IT NEEDS TO LIMIT THE AMOUNT OF VACUUM ALLOWED TO THE EGR SO THE EGR DOESNT OPEN TO EARLY. WHAT CAN I DO ABOUT THIS?

Thanks!