I want to add a backup camera to my 2001 LS 430 non-GPS car. Would like to hear any recommendations.

 

Search button.... this has been covered extensively

 

Check my build thread... covered it there.

 

I did similar unit / camera combo. I made a post about running the camera wires in the trunk. What pin for the reverse power ON and the ground lug was close in trunk as well.

But basically pop passenter trim along door sill, remove back seat and install the antenna / Adapter cabling and wire in the trunk. Not challenging, just need to unbolt/install/reassemble.
I also presume you'll need a beatsonic adapter to make the headunit work. But its simple to crimp and install the beatsonic. Woirks perfect with our older cars!