talk with an installer about the parking brake bypass.Most say it can be done without having to spend an extra 20 plus dollars. You will need the steering wheel controls.
Will I end up losing the functionality of USB/AUX on the truck? I believe the HU has it's own USB.On my HU, I've just grounded the parking brake wire so it always thinks the car is parked.
If the HU has a USB and AUX from the back the HU, you'll have to integrate that into the existing USB/AUX in the truck. It won't be a direct hook up.
Thanks for the advice.I was able to reuse my usb port and connect to to my Pioneer headunit. I took an old usb cord and cut off the end, and stripped back the leads/insulation. I used a multimeter to figure out which lead to connect to the Toyota USB jack (after cutting those cables), soldered the connections and followed up with heat shrink. Works fine.
The aux desn't work, I didn't have a good place to connect it on back of the headunit.