You'll want to "pull it all out", the vacuum and PS pumps as a unit, anyhow. If you just pull the PS pump it's a booger to do and its' connection to the PS pump involves a round connector plate that floats in it's housing a little and may drop down when disconnected and prevent re-assembly, until you have the two pumps out on the bench up-ended so that when you position the plate so the dogs ... More @Wikipedia
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