I think I have it figured out!
I going to have to throw out the traditional SW spell book. While I can hear the howls of indignation from the Savages, I really can't think of any other way to handle the magic in this setting. So many of the spells have no direct SW's analog that it's ultimately wiser to start from scratch.
OK, the spells have all the basics: Rank, Power Points, etc. Many spells have have various levels that can be purchased using one of the level up options provided the character reaches a particular rank and/or has the right religious affiliation. Some spells are "Temple Spells" where your PC must get permission from their Temple (not an easy thing) or receive the spell as a reward from some service. Spellcasting will have one skill. To cast Ritual Spells PCs will have to met certain requirements while Psychic Spells will just require line of sight.
Magic is going to be VERY powerful. Most of the combat spells can kill an Extra outright. Wild Cards will have a chance to save.