your always thinking chris.

you could just mount one verticle in the center like the sail boats do it.

The Fountain is a single step 29 Fever F1 and the Venom was a twin step 32 ZXR F1 Both have notched transoms.

When you run the tabs straight across, it gives the idea of possibly adding some length to the bottom with out scrubbing as much speed off when tabs need to be used in various conditions. Is this what the Arneson rocker plates do? Thanks Jeff

Tantrum, which way should we install them on the NEW SBRT underwater secret weapon

Imo basically the same thing but I think Tabs horizontal work better.
Discussed this with some offshore 2 liter racers recently and came to this conclusion.
the thought behind this was that the tabs and the running surface of the boat makes a triangle which is the most effective way of stabilizing.
Feel free to correct/inform me.

Correct...I saw boats back in the '90s doing this and I'm sure they were doing this before that time too. I saw Bob Bull's F1 Velocity back in 1997-98 with tabs mounted like this...also Miklos and Gary from the F1 Oatey boat played around with tabs a lot from inner to outer mountings as well.