[Shotimes] power antenna question

[van Oss]

I am installing a JVC head unit in the 92.  This unit provides just one
12vV+ output line for controlling accessories.  Methinks I need two:

1.  12V+ to power antenna module to control automatic antenna up/down.

2.  12V+ to main JBL amp in trunk, to turn it on.

I suppose I could tie the amp and antenna together to the single line from
the radio, but that seems like questionable practice.  Another option would
be to use the radio's output line for the amp, and put in a manual switch
for the antenna.  Kinda Gen1, though.  ;-)   Any suggestions?

Joseph van Oss