How to Megasquirt your 3G Hemi

Is there any reason you could'nt use the factory map sensor? Still kicking around WTH im gonna use but I have an 04 Truck harness and has the wrong coil plugs and cam sensor plug for my 6.1. Im also curious if the MS3 Pro needs coil drivers? I still cant swallow going the OEM route then needing an email tune.