My 233 Formula has twin engines and therefore not much transom area to mount K planes or high performance tabs. Additionally, the transom is stepped on a 233. I'd like to upgrade to k planes or similar but only have about 12" on transom and also need to have drive clearance. Anyone out there have any experiences with this?

Maybe have a plate machined that will contour te step, then bolt that and the tab together, then to hull.

I had a 1979 yellow 233 with a single 350 / 300hp. Mine had Bennit tabs on it. There not as big as the K planes, but they they will it in the space you have on the transom. They worked out well for me, and never had a problem.
I also had the swim plat form on mine.

i had bennetts on my old 233, worked fine for the boat- good luck -jeff