Hypothetical question regarding removing catalytic conv.

I realize that california is restrictive. And we live way up in Northern california, the part that hopefully will become the State of Jefferson but that is for another thread. We do not have emission checks here.
In 1 year and 7 months Patti is retiring and we will NO LONGER be residents of california.....Will hopefully be setting on residency in IDAHO, where sanity reigns.
I was just curious from a possible savings view point.