Carter ASB question please???

[sportster]

Anybody out there in the know if these venturi vent holes go toward the front of the engine or rear , thanks and double thanks if you know for sure.

 

[62MAX]

The bottom of the booster is notched,they'll only go on one way !

 

[sportster]

The bottom of the booster is notched,they'll only go on one way !

I guess I totally do not understand as I have reversed the secondary venturis in either side with no problems on 3 different stock carbs and any pics show them either way "so do the holes go in the front or rear was my question"???
Remember if you answer correct u win and I win Thanks Dude.