GM AM/FM/CD Power Antenna

Ok...the 78 Electra Wagon has the factory AM/FM/CB power antenna...and it's currently down...I've never seen it move, since the radio was no good. I found the way to test it, see here:

Power hookup for testing....
To raise
Green(+) Gray(-)

To lower
Green(-) White(+)

SO knowing I'm installing a new aftermarket Kenwood this weekend, is it possible, if it works, to use the original antenna? I know the antenna wire will plug in, but how do I wire this thing? I'm thinking the aftermarket radio will just have a single power wire for the antenna.....

Thoughts? Tips? Anyone done this?

Facebook is amazing...   I just got this in a Message:  The grey/white/green wires work in conjunction with the relay to raise and lower the antenna.
no single wire is for raising or lowering the antenna.
For up....
green (+)
gray (-)

For down....
white (+)
green (-)

What you need to find in the vicinity of the radio are orange and yellow wires.
The orange is constant hot, allowing the antenna to go down when the car is turned off.
Yellow is the TRIGGER that should go to your new radios antenna lead.