On the road again!
The copper bolt to which the battery leads is a bit loose or sloppy likely related to the small piece of plastic that was missing. The nuts are now tight and the engine fired up straight away. The P0335 and P0340 codes are gone, indicated voltage is steady but lower than I'd prefer, at timed dipping to 13.6 and up to 14.2 when driving at highway speeds.
Thanks to all who offered suggestions and answered my questions.



