Hey Chili,
I've got a '95 E-320 Special Edition!
If I'm correct, the difference is this:
1. available in spruce green paint
2. six hole wheels usually available only on the E-420
3. burl wood on the dash, doors, and center console instead of the zebrano
That's the only differences I know of. It was really more of a "package" available when you buy the car.
I bought mine last year with nearly 120,000 miles on it and have been very happy with it!
Hope this helped. Welcome to the board!