Also answered at your post in FS2004 forum.
It is not only possible it is essentially what the Baron Lite uses and what makes the DF Baron Lite compatible with 64 bit operating systems (The same principals also work with the Dreamfleet Bonanza A36). I made the changes myself quite a while back (although I now use the Friendly Panel GPS instead of the default GPS) and it works great for me.
You need to make some changes in the panel cfg found at Flight Simulator 9/Aircraft/DreamFleet Baron 58xp/panel/panel.cfg.(Be sure you make a backup of your original panel.cfg before beginning.) Then make these changes:
Everywhere you find this entry:
Change it to read:
Now you can fly with GPS and without all the error messages.
"...eyes ever turned skyward."
Alienware Aurora R4, Win7x64, Intel i7-3820 @ 3.6ghz/4.2ghz turbo, 8gb RAM @ 2133hz,
Nvidia GeForce GTX580 @1.5gb, 1TB SATA @ 6gb/s, Intel 330 120gb SSD for FSX