ON my 87 TII I have 4 Vac nipples on the back of the UIM there is a small one a bigger one for the OMP vac lines another smaller and another smaller one

today i was looking at rotaryresurection.com and came across this pic where it shows the little 90 degree vac line with the green ball thing on it going to the top nipple is this correct mine has always been in the very bottom nipple? where does it belong?

 

that's for the double throttle system. it's not needed. you can use the bottom nipple as a vacuum source for a BOV, boost gauge, or whatever. Or you can cap it off.

 

do i have to cap off where it attaches to the throttle body?