Both of these MBWs are gen powered. I had to shave a small amount of metal from the calendar ring on the 1575 to get it to fully seat into the case & grind a small flat spot on the pillar plate to give the Hev clearance (note - the gens do likewise). Otherwise, both 157x movements fit their respective (3+ year old) MBW cases without incident. They have also been fitted with gen crowns/tubes, crystals, bezel/insert/pearls, handsets & bracelets, so, excepting their dials (both of which are modded non-MBW aftermarkets) & MBW mid-cases, they are nearly gens