All I;m saying is the less electronics, IMNSHO, the better. Backfitting something to track mileage on an older vehicle is going to be interesting. Much like catalytic convertors and trying to enforce the law in 50 states. Since there’s no emissions testing in this state, mechanics DGAS.
A standalone electronics unit added to an older car can be beat.
Actually, it’s easier in some respects. You permanently mount some box that just needs a 12V feed.
Later cars, they’ll have to either use the same box or do something that is compatible with the car (good luck with that).
Me, I have Jaguars. Nobody will ever complain or suspect otherwise when the old Brit car chews up and shorts out whatever they fit to it.