Mega Gun fin placement

Ok not strictly a surf gun but a 17’ x 23 down wind pin tail ocean crossing machine which I am building. I normally only run a single fin 24" from the tail but would like to experiment with other setups so want to throw a load of boxes in for 2+1 thruster and maybe quad but un surprisingly there’s not much info out there. Any words from the wise that could help me get them about right?

Ocean crossing paddle board is a different animal than a big wave gun.

kinda but was the closest thing I could think of, we surf these boards too so they need to be able have some control as well as just direction and I thought I may stand getting a few numbers for a 10’ or 11’ gun to work from that would probably be more useful than a 9’ longboard.

there have been past threads on big wave gun fin placement, but I don’t know if any of the information would apply to an open ocean paddle board, I’ll see if I can dig up a thread and bump it.

cheers many thanks huck, I guess at worst I will just have to go off a long board which are basically how the board wants to feel however just nearly twice its length and then just move things a little forward or just totally free style it and go with what looks about righ

At 25 inches for a single fin; you should have enough room to put a variety of multiple fin systems just about anywhere on that behemoth.