'88 5ksq-Radio Install

[msr11@psu.edu (Matthew S. Robinson)]

In the process of installing a new head unit in my '88 5ksq-I encountered a
few wiring questions.  When looking at the original harness:

1)Why are there two blue leads (one for power antenna, but the other?)
2)I assume that I should connect the red and yellow leads from the new
harness to the original positive(red and white stripe)-to maintain always
on status...
3)What is the _white_  lead for? Some sort of illumination for the original
unit? (all I can get out of it is 1.5v when the lights are on!)

Thanks for any help,
Matt.