[jls74formula455]

I have a L-75 455 with the factory ram air set up as ordered when new. The original intake is back on my car and a correct numbered & dated previously rebuilt carb gone through by Mr. C. Ruggles is about to follow. My very experienced classic car mechanic who makes house calls recommends that I re-install the EGR for proper idling. I got an EGR from an original '75 350 4bbl Firebird motor (see pic). My intake looks like the one on the SD motor pictured, lacking that black fitting by the thermostat housing as seen on the '75 motor (it looks as if the vacuum line from the EGR goes to the black fitting). Does anyone have a diagram that shows how the EGR is supposed to be set up for my '74 intake? My '74 shop manual diagram shows that black fitting by the thermostat housing (???).

Does anyone have any experience with blocking off the EGR on '74 Firebirds and its effect on idling?

Can anyone tell me how many vacuum lines should come off the back of the carb and where I can find the correct "branch" fitting that screws into the carb where all the vacuum lines are connected to?