not too sure i would trust anything like that that clamps on with the pounding the boat would get. maybe get one made up that will slot into something like rod holders on the side of the boat that will run up and over the top and would be more stable than clamp on , prob is you would need to get a custom made model to suit your boat. 

 I’ve recently brought one for my runabout from whitworths, I needed to get the bars that join to the Bimini bent so that it cleared the back edge of the Bimini, but fit well once I done that. I’m happy with it, it’s only as strong as your Bimini is tho, I don’t travel with my rods in it, I leave them in rod holders or on the deck, just put them up there while trolling or fishing to keep them out of the way. Works great for that. I keep my runabout in the garage too so good up and down every time I use the boat and takes bugger all time. 

They're great until they're not.

fishwrecked.com/forum/free-jigging-combo.

If you're going to go down that line drill out the cross bar holes so you can lock it in place with a bolt and locknut rather than rely on the self tapping screws into the nylon end piece. I never really trusted those clamp togther knuckles as the only attachment point to the bimini frame either.

 if this would clamp to your bimini then I recommend it mate- I had to adjust my cover to suit but it's great- I have no idea how they can produce it for the price!

www.theboatwarehouse.com.au/fishing-accessories/rod-holders-lure-holders-gear-racks/rocket-launcher-with-clamps-holds-5-rods/

thanks guys! good tips and much appreciated!

I got the oceansouth one from Whitworths, and whilst it is actually quite strong and well made, it does rely on whatever its attached to for its strength.

mine clamps to the bimini frame, and therefore is a bit wobbly, especially when loaded with heavy trolling gear in a bit of rough weather.

otherwise, it is well fit for purpose.