You probably have this figured out by now, but in case... First, vacuum lines which aren't used generally function better when sealed air tight. Golf tees followed by electrical tape is generally pretty good for this. Secondly, I would check out your local junkyard for a truck you can take notes from. It would be the same year as your engine so you can see that connection, then transfer the function to your year vehicle. That helps me. A friend with the proper truck would be quite helpful also.