I'm still using the official 5D with a Mega at the moment, but I'm going to try out some other firmwares with this build as soon as I know it's all operational.
Boxed up wiring.
Pololu Stepper drivers added with small blue heatsinks added
Testing X first.
Opto's tested and all working
Fan added to cool stepper drivers.
And finally the extruder hot-end all wired up and working. Note the red LED so I can tell when power is being applied to the heater block.