Trxstle + Beef Rack?

Has anyone found a solution for mounting a Trxstle fly rod carrier to the beef rack? The bars are too beefy for the clamp system that comes with the Trxstle. It seems like a U clamp over the rod carrier bolted directly to the t-nuts might work?

Anyone got a way to mount the Trxstle to the bars, and is willing to share? Much appreciated!