making an autonomus water sampler boat

Hi.

We have an Riverboat SP from Oceanscience 

http://www.teledynemarine.com/riverboat-sp?ProductLineID=83

and we are thinking in transform it in an electric RC boat to research applications in quiet waters. 

Specifications: Center Hull Length 121cm (48"); Overvall Width 81cm (32")
Empty weight 7kg (15lbs), Maximum weigth (with equipment): 12 kg (24 lbs)

Can anybody help us to choose the best option to make this job. We are thinking in install two Waterproof Underwater Thruster Motors and RC.

Thanks in advance

Guillermo