Side Note: In NJ, they offer a senior discounted rate on the Turnpike & GSP. It is also offered by the Del. River Port Authority bridges. (none to NY) You can only have one transponder registered for the each Senior though. So, you need to take it from car to car, which you can do in NJ without difficulty.
I switched between vehicles without a problem before I got around to adding my new car to my ez-pass account.