How to adjust LOD rotation?

So an asset I bought from the Marketplace was rotated along the wrong axis (using as a spline mesh) so I exported it, set the Import Rotation to 90 and then reimported. This fixed the rotation of LOD0 but the rotation of LOD 1 is still incorrect. How can I change the rotation of the LOD? There’s an option for adjusting the scale but not the rotation. You’d think I adjust the import rotation that it would update the rotation for all LODs automatically as I can’t imagine a circumstance where you’d want the LOD to be at a different rotation from the base. This is especially frustrating because there’s no option to delete LODs or export them so I can adjust them manually.