I can't remember the exact steps at the moment but I think I used
https://www.extranslator.com/
https://www.polyphone-soundfonts.com/
https://www.pgmusic.com/forums/ubbthreads.php?ubb=showflat&Number=409007#Post409007
or
This is included in free LinuxSampler to convert gig files to wav.
Gig Extract to wav (from Free LinuxSampler Mac/Win)
https://www.dropbox.com/s/6p79lsjwpm4ugj7/GIG2WAV-WIN-MAC.zip?dl=1

I would much rather pay for the soundfont than make it up again.