I donīt know the SD1, but if is has got instrument-banks this should be possible via simple revoicing.
e.g.:  ( from my Audya, but in principle itīs useable to all keyboards! )
MIDI-Original ( MSB,LSB,PrgChange ):
Grand_Piano = 0,0,1
GM2 Voice instead : Bright_Grand = 0,1,1
For those who have a Yamaha-keyboard : Use 
PSRUTI (freeware, scroll down for english version), itīs very easy to revoice standard MIDI-Voices by Tyros-Voices.
With the "Midifile Optimizer 7" from 
MIDILAND ( 150  ) you can do it as well very easy, it has the soundbank of the sd1 and sd1 + ( and Audya ) built in.