Wondering what some common fin placements are for a twin plus trailer setup. From what I've found it seems the front fins are generally set around 8.5-8.75 and the back fin is set at a standard thruster postition. In the board I am currently making I would like to mostly surf it as a twin plus trailer, but also be able to chuck in a standard thruster set when the waves get larger. Was thinking 9 inches for the rail fins, with 1/4 inch tow, and 3.5 for the center fin. This sound good? I'm at a little bit of a loss for how far to set them off the rails. Any input on twin plus trailer fin placement would be greatly appreciated. The board is 5'8, 19 1/2, 2 5/16 with a modern twin fin outline.
As always, thanks in advance.