The MAC 500 is too big to fit in original MAC 600 flight cases. Only flight cases produced after the MAC 500 was introduced are large enough to fit either fixture. Transporting the MAC 500 in a MAC 600 flight case will result in serious damage to the fixture.
The original MAC 600 flight case measures 860 mm (34") from bottom to top, including wheels, on the outside. The MAC 500/600 flight case is larger: it measures 894 mm (35.2") from bottom to top, including wheels, on the outside.
We suggest that you place a warning label that reads "For standard MAC 600 only! Not for transport of the MAC 500 or MAC 600 fitted with 18° lens hood." inside the MAC 600-only flight case.