I'm assuming you are referring to a Mopar E-body. You can if you have the time, money, energy, knowledge, and skill. The unibody is the same but there are some stiffening pieces added to convertibles. If you hack off the roof without adding these first then the car will likely bend in half. There's also a bunch of supports near/around the rear wheelhouses to hold the top assembly. Your best bet is to have a parts book, factory service manual, and a whole bunch of reference pics before diving in. There's obviously a lot more to it than I wrote but it is possible.
Troy