Just to add my two cents' worth to the varnishing issue:
A few years back I stripped all the old varnish from the entire interior by applying a vanish-removing gel. It came off easily and after lightly sanding the bare wood I apllied four coats of Epifanes Rapidclear, a satin varnish that needs no sanding between coats. I use this varnish for both exterior and interior surfaces and it holds very well in the very unforgiving sunlight we have in Greece. However, on the lower part of the bulkheads which are hidden by the bunk tops, I applied clear epoxy resin instead of varnish, in order to seal the wood for good. On most Ballads I've seen, these are the parts that tend to remain moist and rot.
I considered doing what Frank did but didn't have the nerve. After seeing his photos, I have to admit that it looks great. Apart from brightening up the interior, they are easier to maintain. Also the off-white contrasts very nicely with the wood trim. Well done, Frank.
Nicholas
Moments of Clarity #334