Take a look on the Rimmer's site where you can find out part of the answer, although note that the rear glass is also called a 'rear-window' or 'back-light', not a windscreen, otherwise you won't get far. For all the information you need though, and probably answers to other problems you have mentioned, you really DO need to to join the MGOC (if not already a member), and then ask for full membership to the Two-Sixties here. As a 260 owner, there is then no extra fee, but a whole load of help. The info simply will not be available to you otherwise.
Sorry if that sounds a bit unfriendly to you, and certainly not intended to be, but I believe it's good advice. OK, as a fixed-income OAP I can't be cavalier about these kind of things, but at about fifty quid, I believe MGOC membership is a bargain worth every penny, and opens the door to a Two-Sixty treasure-chest.