Seafoam

I want to Seafoam my 1999 Alero, 3.4l, 6 cyl. engine, and suck some into throttle body to feed all 6 cylinders. What vacuum line do I use (pictures please)?

Best to put it in the rear pass side of the intake.
thier is a rubber cap over the vacum port, some use the PCV but that doesnt go into the intake.

The yello circle by the alternator is where the vac port is located.
http://i28.photobucket.com/albums/c242/xeroinfinity/auto%20odds-ends/Vacumports.jpg