Magnaflux is finished. We needed to check the ribs; both top and bottom have major gaps in the solder joints. This is easily fixed. Two other areas concerned me:
This spot is 4" back from the muzzle on the right barrel. It Magnafluxed OK. The other area:

This area is 13 1/2" up from the muzzle. Bad news:

There is a small crack or separation in the laminate indicated by the thin red line. I would not use this barrel set as is. Relining the barrels is an option. Separating them to use the left barrel as single barrel fowler is another option. It's a beautiful barrel set having very clean bores. I'm not ready to give up on them yet. Further opinions of the assessment?