Most Honda trunks have about three different tension levels for the bars that hold the lid open. I imagine this would also apply to the trunk lid. If this is the case, you may be able to move the tension bars to the next higher level in order to support the additional weight of a bed liner. If the Ridgeline has these, and if you try to adjust them, BE CAREFUL as there is alot of tension built up in those bars and you could get hurt. I whacked my knuckles pretty good with them when I was installing the new bars for my spoiler, and damn near hit myself in the face, so either get the tool through H&A, or use some vice grips. I recommend the tool over vice grips though.