I recently acquired a Heintzman upright with the Metalnola action,
in very clean condition.  I wonder does anyone have a tubing chart?
I have the original service manual but it doesn't include the tubing.

The finger buttons and stack cut-out are easy, but the tracker and
other features all go through a sliding junction block behind the
spool box and it looks like an explosion in a spaghetti factory
back there!

Thanks,
Tom Binnall