How do I adjust the idle on my 1985 Ford Econoline E-350 van?

Iv'e done this before on my 1994 Ford Escort Wagon. All I had to do is turn a screw on the engine.

I pulled of the plastic motor console in the cab, and found where the gas pedal cable ends. I believe I found the idle screw but I would like a diagram or page from a manual to comfirm what I am thinking. I would rather do this once the right way, rather than complicate the matter by messing something else up.How do I adjust the idle on my 1985 Ford Econoline E-350 van?To properly adjust any carb you need a tack meter and a timing light. As you change the rpms you change the timing as well. (those weights in the distributor remember those) as the rpms increase they expand and advance the timing therefor needing to tun the distributor.