Rx330 Aftermarket Nav / Rear Camera Help Needed

[jnj30]

Hi. Brand new to forum chat, your patience is appreciated in advance.

I have a 2005 RX330 with factory navigation / backup camera. Installed a Kenwood DNX-890HD and CMOS-310 backup camera to replace, well, everything I could replace. Finally figured out how to retain temperature control, but struggling with a couple of things:

1. When shifting into reverse, the vehicle tries to revert to the factory backup camera, which has been removed (factory nav screen goes to gray and the Kenwood does not switch over to camera mode). Is this correctable?

UPDATE: I'm now able to shift into reverse without the factory nav screen going gray. BUT I'm having trouble getting the Kenwood to switch to the camera when shifting to reverse. Help?

2. UPDATE: not sure how, but I was able to remove both the Park Assist box and Nav computer, so far, everything else seems functional. I'm thinking that removing the Park Assist box fixed the updated fix in #1 above.

The plan was to remove all the factory components and sell them to recover some of the cost of the aftermarket system. Realized quickly that I couldn't remove the factory nav screen (wanted to replace with the non-nav display to retain temp control options, see #3 below). I disconnected the Parking Assist box (behind rear right side panel) and the navigation computer (under storage tray in the back) only to cause myself more problems (now realizing EVERYTHING is interconnected on these vehicles. Is there a way to re-route or modify the system so I can remove these two components and not lose other features? (Hoping there is a workaround for this as there was with the temperature control running through the factory radio before displaying on the navigation screen.)

3. Still need help with this:

Has anyone figured a way to adapt the factory wiring of the factory navigation screen to work with the correponding factory non-navigation dash insert (contains temperature control buttons and display only)? There are three connections on the back of the navigation screen unit and only one on the back of the corresponding non-navigation insert (temp control) and (surprise!) none of the three hookups from the navigation screen remotely resemble the one hookup on the temp control panel.

Any advice or possible resources would be greatly appreciated.