Rear Vacuum Port
Drill Rear Tab in center with an 'R' Drill .339
Drill thru as shown
Using an 1/8 NPT Tap -Tread the Rear drilled thru hole
Install the 1/8 NPT Fitting into threaded hole as above

Using a wrench tighten fitting

For Use of the Pressure Relief Valve or other Vacuum needs
Do this when Installing larger fuel system.

Click on pic to make larger