Lets also not forget the prones of the Q-jet....

1) Take off the air cleaner and stand over the carb and actuate the rear air door open and closed. As you are doing so pay close attention to the rod hanger that pulls the rods out of the secondary jets...You'll want to make sure that both rods are hanging on the hanger.....

They are prone to fall off if the hook isn't fully bent.

2) secondary emulsion tubes....These are prone to fall out! usually just one side and will run with surge like symtoms just like a fallen rod... Fixing will require pulling the top off the carb....

Listen to the engine when it's doing what is doing. It will tell you wether it's lean or rich...

If it seem to run smooth while surging and pulling then not pulling.....It's lean

If it's crakle-ing while surging and not pulling.....it's rich....

It is very important to have adequate fuel pressure at all rpm's when you tip open the secondaries on a Q-jet....

Later one if you still have trouble we may have you pull the rod&hanger and list what is on the rods and hanger.....

Funny thing...Did you know they actually put Q-jet on early Mustangs....I beleive the 67-69 427-429 units....I have one is how I found out....It should be listed in your book Denny....