I'm not sure about your questions 1, 2, and 5, but the quick answer to 3 and 4 is: None.
No Challengers were built at Chrysler Newark. They were all built at either Hamtramck, Michigan or Los Angeles, and the LA plant ONLY built hardtops, as I recall. The seventh digit of the VIN tells the manufacturing plant: B for Hamtramck, E (I think) for LA.