Jay - when you took out the air pump what did you do with the block that went into the head?
Did you change distributors that had the vacuum line running from the EGR valve to a single vacuum line distributor?
Just block off the pipe that ran from the EGR to the throttle body?
remove the EGR switch valve?

All the questions as I am switching out manifolds and see all this stuff that may not be needed but want to know what to do with it.
I di have a distributor hooked up to a Crane system that only has 1 vacuum line but know the 75 has both vacuum advance and retard.