I have made some custom mpguinos where buttons are in separate small board (and buttons-in-top version) so you can flush install mpguino and put buttons somewhere else.
I have also made custom code just like I like it
extra features:
* added metric version (must choose before code/firmware uploading, no change possible in settings)
* bargraphs (shows 2min average 5-9L/100km - dropped 0-5L to gain better resolution)
* battery voltage
* trip cost (in settins you enter fuel price)
* tank and current trip time in hours.minutes
* saving tank trip data to eeprom (dont forget it when disconnected)
* some values are shown in integers (speed, rpm)
* removed leading zeroes (instead "012.45" shows " 12.45")
* added dragrace screen (0-100km/h time, 400m time and trap speed, calculated horsepower)
* using Atmega chip sleep mode (consumes about 5milliAmps versus 20milliAmps when in sleep)
here are some pictures:
MPGuino - Meelis P
Mpguino is built in custom etched PCB and is same size like LCD (sits behind it, electrically it is compatible with "official mpguino"). I am using atmega 328
I think it would be around 59 euros + shipping. I have some pre-built MPGuinos at home
Meelis