Hi guys,
we are currently in the process of installing a Weber 32/36 on an A12 and I'm just going through the process. The carby is mounted and the throttle linkage is done. Looking at it closer though and comparing it to the pics I see of everyone else's, We have 3 different fittings for the fuel supply.
Since I don't particularly specialise in carbies, I can't work out why we have three and most people have one. Can anyone tell me what is what?

So in order:
(1) Some people have this on an angle similar to 2 (is this fuel?)
(2) Some people run their fuel line into this (is this fuel?)
(3) This looks like some sort of air line but I'm not sure if it has vacuum in it (or much)
(4) is this good for the vac advance to the dizzy?
Do I use one and block the other off?
Any help would be appreciated.
Thanks guys