propping a 6.5m ballistic dive boat

[Donnie144]

I have a 6.5m ballistic boat on its way. It will be rigged with twin Nissan 90’s. The boat weighs in at approx. 440 KG the motors combined come in at 286 Kg. With fuel and 6 divers I will be adding approx. another 550-600kg. What type of prop, material and pitching would someone recommend? With two motors it makes the trial and error method bloody expensive.