PAIR system vacuum source question

[mik_str]

As I don't have my spare set of carbs handy at the moment, I was wondering if anyone here knew where the vacuum feed for the PAIR system is located inside the carb (I know the outlet tube for it in on the outside of the carb, but where does it gets its vacuum from?). More precisely, is it on the engine side or airbox side of the butterfly? No speculation please, am looking for the real answer (may have an interesting project to share with you depending on the answer)

cheers