Imagine the price for propane if everybody converted? That's what will happen with electricity if JT gets his way.
As for the catalytics, you'd have to by-pass / fool the rear O2 censor. When I had my '87 Buick Regal, that's what I did, but for more power. (free flow exhaust)
If you like diesels, best to get 2009 and older. Less emission controls and censors. I would not buy a new diesel anything.