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I did it for gxp but it works fine. The Shimano will be the same but both cups will have the same ID I guess. You get the cups and then thin spacers you can use to get it centered.
When I got the new caad12 frame it came with one of the proper wheels mfg bottom brackets which threads together in the middle and it is so, so much easier than the shims.If you can stretch to it then it's definitely worth it, I'd say. https://www.sigmasports.com/item/Wheels-Manufacturing/BB30A-to-Outboard-Bottom-Bracket-for-24mm-Cranks/
Or a cheaper version
https://www.wiggle.co.uk/token-ninja-cannondale-bb30a-shimano-24mm-bottom-bracket
The shims are about £25-30.
those plastic / nylon ones over bb30 bearings? i think @dglshrn had success with it