Not that easy at all, Meldric
I know it, i have done it for all Dark Water U-Boats, it’s huge work.
Not only adding water spray nodes all along each hull sides, but you have to make corresponding effects in particules.dat and materials.dat!
Can tell you it’s not just few things to add here and there...and after that, you have to test it in all situations
If i remember correctly, was more than a month work each day on it from morning to evening (to me at least)