The MAVIC bottom bracket used sealed cartridge bearings, so unless one is notably gritty, there is no need to remove the unit.

Having said that, the unit did come in French, English and Italian versions. Both the French and Italian. versions used locknuts on both sides (i.e no cups). These versions were not threaded into the frame, so once you remove one locknut, the entire unit will slide out. However, the English unit used a threaded cup on the drive side that is threaded into the frame. You may need two lockring spanners to prevent the tendency of the entire unit to spin in the BB shell.

If you need to replace one of the cartridge bearings, each end has a cap that is threaded into the aluminum sleeve, to hold the bearing in place. The caps are removed with a pin tool, such as those used on standard adjustable cups. It's been along time since I've worked with one, so hopefully, I've remembered things correctly.