What's the Difference? Rear Beam Z3 v ZM

[Pingu]

33312228200 = ZM rear beam
33311090957 = Z3 and E36 rear beam

Does anybody know the difference between the two rear beams?

 

[NZ00Z3]

By memory there are 2 differences. The Z3M has:
- A different angle of trailing arms mounts
- Internal "I" beam to make it stronger

 

[Pingu]

By memory there are 2 differences. The Z3M has:
- A different angle of trailing arms mounts
- Internal "I" beam to make it stronger

Thanks. I might have been able to modify a beam to suit the different angle, but the I-beam addition rules out using a non-M rear beam.

 

[Nodzed]

M rear beam a godzillion pounds.