The only thing remaining is to clean up the silver-part-to-silver-part solder joints, shine up the silver parts, clean the brass parts, and hit the brass parts with metallic silver rattle-can paint (with a coat of clear).
...so here's the Pan American/14K/36K/22K/38K/Secrist-pistons (sans the thick coat of white paint under the thick coat of blue paint) sousaphone:
cost: two days of paint-stripping, unsmashing, and fitting stuff together, plus c. $250 for a pre-retirement Secrist valve rebuild job.
(no dents)
I'm thinking I'll supply one of those Chinese helleberg knock-offs with it...(??)
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Notice the cast brace from the #1 upper return to the body.
The reason it doesn't fit the old footprint, is because that's actually a 36K (fiberglass) cast brace (found via scrounging) that I reshaped to function on a 14K. I DID find another one (which someone had Z-ed out of some square stock), but decided to go with a factory-made (even if wrong) part, as the solder joint contact feet are so much larger...and I would have had to alter a "correct" one anyway, as I had altered this valve section to have an upper return SLIDE, and not just a fixed bow.
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Thanks to @Nworbekim for selling me the used Conn sousaphone tuning bits.
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The first (and LAST, by me
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bloke "your stuff-from-junk man"