Gordon,  I am assuming you have a roll scanner.  From my collection of
Wurlitzer 165 MIDI file, I have some in tracker bar format (which sound
horrible), some in Mike Ames' "AMI" format, which is universally used
on MIDI systems playing Style 165 music, and also two different kinds
of listenable files.

I personally wouldn't suggest tracker format, unless you only can use
one channel.  Mike Ames' "AMI" format is the best in my opinion as it
is in a correct musical scale, but also has all the stops and traps
(actually in tracker bar order).  I actually used Rich Olsen's virtual
Wurlitzer 165 soundfonts to recreate an automatic computer 'band
organ', and it plays these files.

Listenable files are listenable, but they won't play on an organ.
I have some MIDI scan files that have bells that turn on and off,
automatic registers, and drums also, and some a little simpler that
do have a working 'swell shutter' effect.

I've arranged about 75 songs for the 165 scale, and in my opinion,
Ames' format is your best bet.  If you need the scale sheet, let me
know.

Best regards,
Mikey Mills