Here is a data sheet on the LCD controller. The LCD itself has a 5x10 character format.
http://www.electronic-engineering.ch...cd/hd44780.pdf
One of the possible tweaks might be to create custom characters that use the whole 5x8 character box. They could be larger numbers perhaps for easier reading or maybe custom characters to conserve display real estate , i.e. MPG might have this in front of it instead of three characters:
(Note, just realized the lcd is 5x8, not 5x10!!!)
(just using paintbrush at 800% zoom)
I don't know how many user defined characters are on this display yet, however.