Pesocaster unexpectedly came through and emailed me the schem today, so I get to finally contribute something! For your viewing and possibly layout-making pleasure, the factory schematic for the 903:
https://i731.photobucket.com/albums/ww3 ... us/903.jpg
And in case you don't have the Real Tube schematic for direct comparison here's that: https://i731.photobucket.com/albums/ww3 ... ematic.jpg
Enjoy!