Installed a few pieces of plywood and the bottom drip flashing--the plywood is tough going solo! Then Alicia Kenyon Champ came over and helped me get all of it except the top few pieces! Many thanks to Alicia for lending a much appreciated hand!
Why drip flashing? I chose it to protect the plywood, guide water away from the undercarriage, and break up the solid block of siding.
Why plywood over the Tyvek? I needed to save as much horizontal space as possible, but needed siding. If I did this again, I'd use treated plywood, or leave the ply under the Tyvek and do siding with one type of material rather than the various types I have in mind. Treated plywood takes a year to cure, and it would be that long till I could paint it... I also don't like the chemicals in the treated ply, so this is still on my ideas board for sure!