I just bought a 67 cougar"GT" a while back. I'm not sure though if in fact it is a "GT". Someone told me how to tell by the VIN#'s. IF the fifth # is an S, it's a 390. If the third and fourth #'s are 93, it's an XR7. If the third and fourth #'s are 91, it's standard. My VIN indicates I have the 390, standard cougar. My car also has single letter emblems "GT" on both sides, with disc brakes. I got the car from my cousin and he installed a 429. I didn't get the car for profit but for pleasure, so the 429 I'm happy with because a few mods wouldn't hurt. Here is where things get screwed, on both sides of the radiator, there are two notches cut out. These notches are to bolt these plates that connect tie rods to the front wheels. On the inside things are even worse. A slot was cut out in the dash to run four gauges across. Then in the back where the holes are to get to the shocks, the metal around that was pulled or cut around to make the hole bigger. This is because the tweak that owned the car before my cousin installed vertical mounted airshocks. There is a bracket that runs under the axle from the wheel to the middle of the axle, which holds the shocks in place. So I got holes in the front frame, the dash, and back by the shocks. I'm in a position to by a 68 cougar with no tranny, or engine for 700$. Do 67 and 68 interchange with no problem? I'm thinking of taking all the good parts from my 67 and swap them on to this 68 if I can? Also would I be able to install my 429 into the 68? And last but no least is my 67 a no hope situation?