The styling is different between the 2 panels but I don't recall the specifics.
IIRC, the XL had a wood grain insert on the panel somewhere. You might think about
joining http://www.galaxieclub.com/ . They would be much more able to answer specific
questions about your 68.
 During the gas crunch in the 70s people were almost giving those big Fords away. I
had quite a number of them from 64-69. The 68 was always one of my favorites. My first
car was a 68 XL, 428 4-speed. :)