I made patterns of the Merc's 280, Hardin's 280S and the Dana HP 1000 series trim tabs. Only one had clearance for my application and that was Merc's 280 K-Planes. I'll take Barnett's ST 12 off, fill in the holes and add the K-Planes ASAP. Thank you all for your help.

You probably already know this, but the only difference between 280's and 380's are the plates. So after installing 280's you feel they didn't make the difference you were expecting you can just change to the longer 380 plates and see how the boat reacts. My money is on the 280's being more than enough tab with much quicker response than what you are used to with the factory tabs.

The 380's would be to long just by the patterns I made. There would be interference between the outdrive and tab. I could have made the Hardin 280S work. I would have modified the inner edge and shortened the front tab width. Then powder coat, not worth it.

They come in handy getting the boat off the trailer onto blocks.