The two grips on the handlebars are prevented from falling down with a rubber cord when you take them out. If you loosen this, you should be able to attach the grips upside down. You would then have to turn the bell and the grip pads, but that is doable. On the brake there will be a screw whose end will be on top (about 3mm protruding) instead of the recessed head. But I don't think that will be a problem.