Key FOBs are vehicle specific and are not interchangable. About all one from another car is good for is the case with your internals installed.

 

I'd be interested in one or two old fobs. Just received the RFID programmer/reader and an figuring out how it works. Have read one of mine am still studying the instructions mostly make sense but in some variation of English I have not seen before. Just would prefer not to make a mistake with one of mine

 

The code is burned into the key permanently. It cannot be changed. It should also be very obvious that keys are not interchangeable between cars...and obviously, a metal key cannot be recut to fit your car.

Daimler-Chrysler was not stupid in designing the security for your car.