Well, to a degree.......

A couple list members (thanks for your help) suggested that I hook my cruise 
vacuum line to the fuel pressure regulator.  I went out at lunch, did the 
mod and went for a drive.  The cruise held speed nicely (I ran the van in 
4th at about 45 mph, and 3rd at 3500RPM (equivalent to about 65 mph in 
4th)).  So i think the vacuum problem is cured.  We'll see what happens at 
altitude.

BUT,

The button functionality, other than speed set, was amiss.  The decelerate 
(tap down) and accelerate (tap up) functions did not work smoothly, if at 
all.  That's ok, I don't use them much when I drive a car with a stock CC 
and they aren't a safety issue.   The resume function worked OK:  I hit the 
brakes, system disengaged and slowed down, then i released the brakes and 
pressed the resume button and it sped back up to previously set RPM.  The 
overspeed shutdown did not work.  This should shut the cruise of if the RPM 
runs away, like if I pushed in the clutch with the system active.  I pushed 
in the clutch and allowed the rpm to increase 1000 rpm rapidly and there was 
no shut off.  When I let the clutch back out, the control brought it back to 
the previously set RPM.  As a note, my system is set up to measure rpm from 
the negative side of the coil, not an axle/driveshaft magnet speed sensing 
setup.

Guess I've got to call Gene at Equus again.

Thanks again for all your help!
Fred Porter