I agree with Gregg. You will need to use twin brushless. Don't expect to use a SLA NiMh's work fine. Lipo's will give the performance of the IC originally fitted. We have several in our club and they all go on the plane easily. I have one to build on the back burner so can't give more details.

I have a Presedent 49 inch version with glass hull. it was purchased secondhand and originally had an I/c engine and single shaft and I presumed it performed well. Unfortunately where I sail we are only allowed electric power.
I have tried twin props with graupner 700bb turbo's and it was very sluggish, no where near planing speed at all. So if you are looking for such, you wil either have to use I/c or go twin brushless motors and a single brushless motor would need to be quite big [for the torque/weight]. its a project Ive sidelined for a while personally, as even choosing the correct pair of brushless motors and prop sizes could be challenging to say the least. But they are a heavy boat with the wooden superstructure, so you do need to watch the wall up weight as you build too, keep it as light as possible.