Hi, I have the 750 and the 2 lines are connected to 1, the lower fuel rail, right at the base of the carb bodies (between carb 1&2), you can route it anyway you like really just make sure it is on tight, that's the pipe from the petcock/tap FRONT/NEAREST YOU when looking at it, 2, the rear pipe goes to the vacuum pipe on carb number 3, if you look at the other 3 carbs they have a rubber cap thingy on them, that's 12&4.
Hope that is what you were looking for, if not I will try to send you a copy of my manual which shows where the lines go.