2008 Prius PAC RP4.2-TY11 instructions please?

Hello, just picked up a nice used 2008 Prius, need to replace the stock head unit. I got the dash kit and the PAC RP4.2-TY11 from Crutchfield but there are a lot of wires here and I'm wondering if anyone has a guide or some tips for installing it correctly. My car does not have the JBL audio, and no navigation. I did search the forums but only found a guide for cars with the JBL system. Thank you for any help you can give me!

 

I installed the system tonight, everything is working perfectly EXCEPT there is no sound at all from the rear speakers. Front speakers work fine, tweeters in the door pillars are working, but no rear speakers. Does anyone know exactly which wires run to the rear speakers from the factory harness? I might try to cut and splice them directly and bypass whatever is going on with the PAC unit.

 

I installed an aftermarket head unit in my car using the pac interface, everything seemed plug and play and easy enough. However I have several weird problems now.

First the rear speakers don't work at all. Not a big deal compared to the other problems.

Second the car no longer charges in park. There are no arrows at all in the energy monitor. The arrows also dissapear briefly when I take my foot off the gas.

Third, it seems like the gas motor is running a lot more than usual, but that may be because it was in the 30s today.

Fourth sometimes when the car is only on electric power my mpg readout is not 99.9 but some random number which slowly climbs to 99.9.

I guess my question is , do the systems that control the functions of the engine, electric motor, etc Actually run through the stereo and mfd or is it just a display which can't necessarily be trusted. Also does anyone have any idea how to fix these issues? Thanks in advance.

Edited to add that the car is a 2008, base audio.