Anyone out there in the know on SU carbs? I am attempting to put su hs6's on my 73 tr6. My question is in how to hook up the fuel lines. There are two nipples on the top of the front carb float bowl, and one on the back carb bowl. Do I run a fuel line from the second nipple to the back bowl, or is this second nipple used as a vent? Anyone out there know? Thanks for looking at this. :confused: