The Jensen 50 is a beast and I hope to have one someday - I'll likely
have to sell my other Jensens to pay for it.
I've had good luck with advice and help from the kind folks at Jensen and
they resoldered a #10 engine 'separated' cylinder/valve-chest for a very
reasonable price - Andy is the miracle worker. I added a video of the
repaired engine running. Later on, I switched the boiler for a complete
one.
P.S. - please add a photo or two from the other end of the boiler.
Good Luck,
Wayne