Assembled shafts

Intermediate shaft does not mesh properly with new centre diff.

New centre diff meshes fine with old broken intermediate shaft

4th gear does not mesh with new shaft either.

But it meshes fine with old broken shaft

These won't go any closer.

New vs old. Note how new shaft on the right has the teeth cut notably wider despite gears being of the same dimensions.

The teeth on the new shaft appear to have a different helical angle as well.