E10 headset to fit Rockshox Zeb

[MrFixit]

Hi, can someone provide info and or a link for bottom headset bearings to fit a zeb with a 46mm steerer into the 56mm head tube? I have looked all over this forum and at several sites for information but can’t find anything. Would I be correct in thinking an integral bearing would be required? I have to admit the variety of sizes and sizing formats metric/inch just confuse me
Thanks