Trying to save a ‘66 Barracuda

'65-6 A-body has the same radiator core support for the 22" radiator (recommended for any engine size). The '63-4 will work also but, only came with a 19" wide radiator. Fine for a 6cyl however. As mentioned, if you get a complete unbolt front end, any '63-6 can be a donor. If you want to keep the '66 look, '66 is unique. Valiant and Barracuda share the same sheet metal up front including the front bumper assembly, but, naturally, moldings and emblems will vary depending on model. The VIN and fender tag will tell you if it's a 273 car or 6cyl. The fender tag will also give you some option info too. The driveshaft will depend on which rear end you have, and which Plymouth A-body and it's rear end is the donor. It's mainly matching the correct length and u-joint size. It's not a big deal getting one too long and having it shortened either. If the transmission crossmember is missing, a '63-6 one will work. The exact one is '65-6. When getting the drivetrain, there are year differences in such things as motor mounts, oil pan, carb, etc. Finding those might be a little more of a challenge as the '67 and newer versions of the parts I mentioned won't work without modification. Once you find out if it's a V8 or 6cyl, and which you decide to install, we can give you more details.