Tom
My car was already registered in MA so there was no problem for me. As long as its registered as a 65 Ford, there should be no problem. Make sure you have a Bill of Sale ready when you go to registry. Mine is listed as a 65 Ford Cobra, and there is no value for that model in the MA registry books for calculating the tax. Therefore, they used the sell price. It will also help to get the Manufacturers Certificate of Origin, just in case.
If you have any problems with insurance, here is an article I wrote to help people in MA.
Send me a PM with your tel # if you want to discuss.