See if this helps http://images.Google.com/imgres?imgurl=http://www.firstgenfirebird.org/firebird/FAQ/docs/vacuum1.jpg&imgrefurl=http://firstgenfirebird.org/FAQ/engine/carburetor.html&h=1548&w=1103&sz=119&hl=en&start=12&um=1&usg=__mxAS0JnxePBRmjiiHWpIeRVBPP8=&tbnid=mq7ITq_Z3ski8M:&tbnh=150&tbnw=107&prev=/images%3Fq%3Dpontiac%2Bvacuum%2Bdiagram%2B1968%26um%3D1%26hl%3Den%26safe%3Doff
I have a wiring diagram /pic for a 72',unable to attach it... but the link below is for a cady club that has links a lot of information.
Ask the dealer for a diagram at parts desk or go to public library and look it it up. They have vacuum and electrical diagram manuals there.
Get a vacuum diagram from MOTORLIT.COM
On the underside of the hood near the front there is a diagram of your vacuum hoses and where they go.
Go to http://ww.mitchellrepair.com
A vacuum diagram shows in detail where are the air lines go on a car. A 1.6 liter Honda Civic engine uses many vacuum lines and the diagram will specify where all the lines are routed. This helps find air leaks on the engine.
ALLDATA OR BOXWRENCH.COM
go to the auto parts store and by a book
go to eBay and look for service manual
It is known as an "Endura delete" option. I have a 1968 GTO with the Endura Delete Option. The 1968 GTO was Motor Trend's Car Of The Year,because of the addition of the Endura Bumper and other safety and styling options. 1968 was the only year you could get the chrome front bumper instead of the Endura,as an option. Standard was the Endura Bumper. These GTO's are very rare to find today as many over the years have been changed,for the better looking Endura bumper. Only about 1,500 of these were built,which is now desirable as production numbers and value go.
Go to the dealer and ask them to photocopy the page for you. Keep in mind though, that half of that system is vacuum contoled. You may need the vacuum diagram as well.
go to autozone.com, they have free pics