All the bearings I can find on civics/crxs are either 72mm OD with 35mm ID or 80 OD with 40mm ID. I need to find a bearing that is 80mm OD (to fit the case) and 35mm ID (to fit my differential)

Unless I can use the 35mm OD Axles in the 40mm OD Differential... Don't think I can. Swap differential internals? Not likely I think.