THe hole in the bottom is the feed out to the plate.. The hole in the side the oposite side of the inlet port is your purge port. If you screw the fitting out of the manafold that goes to the solenoid it will now screw directly into the purge port on the solenoid.
You will illiminate the manafold..(no longer used)
THis will clean it up..
The bad news is that that filter will no longer work. The side that screws into the solenoids needs to be a 1/4 npt.
However you can get rid of that filter and use one of these. http://www.nitrousoutlet.com/catalog...del=78&dept=11
THese filters are best placed at the back of the car..
I hope this helped.