Good luck with it mate, will need to meet up sometime once you've got her up and running. Are you going to keep the E82 on the street for as long as WAPOL allow it? If so, would love to see this thing out for a local N54 drive in the future.
You could consider staged injectors (2x cylinder). Not uncommon for methanol set ups and alleviates the idle issue.
I wouldnt be keen on putting a lot of fuel upstream of the runners because fuel distribution is an unknown and when you go stand alone you will likely be running a single bank wideband, which means each cylinder could be a little more out than they otherwise would be monitoring 3 each.
The only tuning issues related to IAT are tuner solvable. I.e. ignition timing correction for IAT need to be set up for meth and or e85.