There really is a Stillwater, PA (allegedly Gibbs' home town). It is about midway between Williamsport and Wilkes-Barre in Columbia County along PA 487 in north-eastern Pennsylvania.
Shannon's rule no. 1 or no. 3: Never date a lumberjack.
Gibbs makes reference to the fact that when he joined the Marines, the country was celebrating the bicentennial. Assuming Gibbs joined when he was 18 years old, it's likely that Gibbs was born in 1958.
The car on fire in front of the store has a "V" shaped cut on the engine hood over the radiator. That cut is made by firefighters to access the engine compartment when combating a car fire. The car was previously on fire or used as a training evolution.