How to Megasquirt your 3G Hemi
1- crank
2- knock (there's also one on the other side, same spot)
3&4- oil
5- cam sensor
6- looks like water temp area
7- looks like map sensor area
For a megasquirt install, you'll need the factory crank and cam sensors, that's it. The megasquirt also needs these GM sensors:water temp, intake air temp (DIYautotune sells the plugs with the sensors)
And you'll need these: throttle position sensor (on whatever cable TB you use), port for MAP hose (my map sensor is inside the MS3x box), and idle air control (also on the TB of your choosing).
For gauges- use the sensors that match your gauges. Use adapters to make them fit the motor.
What's the motor going in? You should start a thread in the Hemi swap section that shares about your build, we'd all love to see it.