Changing LCD Display info (no replies)

I would like to change the LCD display info.
Not sure where to start... So I'll ask!

Right now I have the default display setting:

Nozzle temp ---- Bed temp
Print Time ---- Z Height in mm
(percent?) ---- Percent: SD
Heating Done

Not sure what the '(percent)' is? But I would like to change this to the
number of layers there are in the format of X/Y layers. (Current layer/Total layer)
Also I would like to add a decimal point to the percent completed.

Anyone know how to proceed with these changes?

Thanks!
Chris