> What about other PCI devices? Will they have to be Mac specific or can
> we use the same cards as the Pegasos?

It depends if the cards have a BIOS or not.

> I was hoping to be able to use thee Soundblaster Live

You know the answer:

https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=6826&forum=11

> and SCSI drivers.

AFAIK, SCSI cards have a BIOS, so you would need one with a PPC Mac compatible BIOS for usage in a PowerMac.