What to do w/power antenna and dimmer wires on install?

Hey folks!

First-time poster here. I just bought a 2004 Prius, and I'm loving life. Except for the stereo without an auxiliary input. Just bought a Pioneer DEH-7500HD, which I intend to install in place of the factory head unit (didn't want to go the stealth install route).

I have a Metra harness, and I am busy connecting it to the Pioneer's harness. All is done except the "dimmer" wire and the "power antenna" wire. Having never seen what's behind the factory unit, I am wondering if I need either of these. I've read some rather confusing info regarding the power antenna wire, so any guidance would be appreciated from those who've gone this route before!

 

Thanks! From what I'm reading, it sounds like the power antenna wire is necessary for the antenna amp. The dimmer seems to have no cousin in the factory harness, so I will indeed cap it off.

 

Hmm--now I'm reading that "illumination" or "dimmer" capability is there. Anyone used this function? If so, what did you wire it to? Does pin 10 on the factory connector attach to the right thing?