John,  yes, the Wurlitzer 105 is tuned a whole step flatter than what
is written on the pipe scale.  The starting bass note "G" is tuned to
"F", and so on up the scale.  Whether you tune to A=440 or A=435 is not
really that important.  The whole instrument being in tune to itself
is important.

The limiting factor I've seen in tuning will be the bass stoppered
pipes.  You can only pull the stopper out so far to flatten the note.
If, for example, you are tuning the bass low "G" to the "F" pitch, and
the stopper falls out before you get there, push it back in until it
is tightly seated, and then use that pitch as your reference point.
It may be a slightly sharp "F" or even an "F sharp".

The reed pipes (trumpets) may have some problem with different pitches
as the resonators are in fact tuned (i.e., cut to length) to sound best
at the correct frequency.  There is some leeway here.

These instruments are solo instruments not meant to be played with
other instruments.  So just like the bagpipe I play, exact pitch isn't
as important as the instrument being in tune to itself.

Jim Quashnock

 [ And, just like the bagpipes, adequate wind is required to maintain
 [ good tuning of a band organ!  -- Robbie