[Gervais]

You could take the bolt out of the angle bracket and use the top of the u bolt sandwiching it between the height adjuster bracket and the u bolt. to secure it which would drop the rear 1 1/2” to 2 “. I don’t think you’d have to worry about it swiveling because the bunk would be so close to the frame it couldn’t tilt much. The pressure on the u bolt should hold it in place. On the forward ones, flip the height adjuster bracke and use the slot to secure the angle bracket with the half inch bolt. This should drop it and you would still have adjustability.

 

[Gervais]

Actually, put the angle bracket on the outside of the height adjuster bracket. This should act the same as the standard bolt that’s in it if you tighten the u bolt enough. You can replace the height adjuster bracket with a “frame plate” for the u bolt. Might take some digging to find a heavy duty one that’s galvanized but that would give more ground clearance.

 

[Gervais]

(8) 10" Aluminum L-Type Boat Trailer Bunk Bracket Kit with Stainless Steel Mounting Hardware For 3x3 Boat Trailer Crossmembers https://a.co/d/gSNFJhi

or something like this and drill holes where needed.

 

[Gervais]

The bunks are turned the other way though

you would repurposed the bracket to function as your existing brackets do. Not mount the bunk differently. If that makes sense