4. Now we arrive at the step that can turn the master cylinder into a paperweight for no apparent reason. Before the master cylinder can be chromed, the sight glass must be pressed out of the reservoir. Since sight glasses and master cylinders are sold as a unit, the sight glass must be removed without being damaged. According to our customizer, a 20-percent failure rate is to be expected. (i.e. Despite following these directions to the letter, for every 10 sight glasses removed, two will mysteriously fail.) The key to a successful sight glass-ectomy is a bolt that has been turned down on a lathe or belt sander so the head is round and just barely slips inside the sight glass' mounting hole in the reservoir. (In the photo on the right, note how little space there is around the bolt head once the sight glass is pressed out.) The bolt slips inside a socket or an appropriately sized piece of pipe, and by slowly tightening a nut against the pipe the sight glass is pushed out. If the bolt head is too small, it will press against the plastic lens instead of the tiny ring that holds the pieces of the sight glass together. Once the part is successfully pressed out, breathe a sigh of relief. If it came out in pieces, buy a new master cylinder and try again.