By now you will have realized that I like making sets of models rather than individual ones. Here, for example, is set of three Boeing 767s illustrating the three main versions of this airliner. All are made from the Revell kit which is not available in the shops and is rare in sway and sells, but turns up on ebay often enough.
The first is the 767-200 series which has a shortest fuselage of the three versions. This is achieved simply enough by cutting a slice out of the fuselage fore and aft of the wings. I don't know how others calculate this distance but I usually do it by counting the windows (frames actually as indicated by the windows) from photos of the model subject. It works out okay. The windows and other details come from the Aviagraphics decal sheet and the Ansett decals came from our good ol' friends at Hawkeye.
The next version is the 767-300 which is made more or less straight out the box. The windows and other details come again from an Aviagraphics sheet and the Australian decals come from a Draw Decals sheet. The decal instructions are minimalist, to put it mildly, so I spent a lot of time looking at photos on Airliners.com in the hope of getting it right.
Finally is a 767-400 which is a longer version than the -300. There used to be a kit, Braz Models if I remember correctly, which can be used to upgrade a -300 to a -600 which includes fuselage plugs, new wing tips and perhaps (my memory is hazy on this) appropriate engines. By the time I was interested in making a -400 this conversion kit was long out of production but I finally bought one through ebay at a more or less reasonable price.
As it turned out, the fuselage plugs were useless because they did not fit properly and required so much surgery to get them into a useful state. In the end I threw up my hands in frustration and then discovered that the plugs cut out of the kit to make the -200 version were just the right size to fill the space needed to turn a -300 into a -400. After that the conversion went well. The windows and other details again came from the Aviagraphics sheet and the Delta decals from a Decales de Guido sheet.
I have another 767-300 kit in my Treasure which I'm saving up to make a QF 767-300F using decals that Mr Hawkeye has in production. I bought the Draw Decals sheet for a QF -300F but it represents the aeroplane without the kangaroos on the tail, and I'd prefer to wait to make a model of the original with the kangaroo. I'll put a photo of it here when it is finished, if I remember.