Lowes, 1/4 NPT to a 1/8 barb.

 

Yeah but there is already a line attached to the drivers side on the intake manifold, there needs to be two lines to tap into the one hole

 

There should be a few ports on the intake, look and see if one is plugged, if so, unplug, buy nipple fitting, win.

 

cut the line that is already there and put the T into it. Run the new vacuum line to the other side of the T. The second line from the dizzy goes to a "port" in the intake tube. I think you may have to drill a hole in the intake tube for this line. The instructions will tell you where to drill it. I have an aftermarket elbow with a port in it already,that is where I plugged mine into

 

every lt1 on the drivers side has 3 vacuum ports in it. if you had a non-vented opti, there will be a hope with a 1/4NPT pipe plug in it.

that is what you want. a tee is not the best solution.

the opti vent is a vent line, and does not maintain vacuum, it is actually a controlled vacuum leak, so it will reduce vacuum on whatever line you're teeing into.