So - onwards and upwards. I set the starboard wing aside and turned my attention to port.
None of the rib stumps were big enough to provide support for the new ribs, so they all came off. Afterwards I prepped the main spar, planing off all of the remaining stubs and any glue.
After a couple of not-so-great attempts at making a cardboard template for the ribs, I removed one of the two intact ribs to use instead. That did the trick.
Shortly afterwards all the ribs were in place, supported at the base by tri-stock. I made a mistake, though...
... I cut the ribs in the wrong grain. I fixed that later.