Mount storage chest on TT bumper
I want to install a bumper mounted 2" receiver, with a swing away mounting platform and storage chest on my 38' 2015 Lacrosse 330RST Travel Trailer. Probably will be 300 - 400 pounds all together. I do not plan on towing with it mounted. It is only for use at our seasonal site. I've seen brackets that bolt to the frame extenders and straddle the bumper that they claim increases the bumper capacity to 500#, but they are for "I" beam style extenders that you can bolt through the extender and bracket. My TT has 4" square extenders welded to the bumper. Is this stronger than the "I" beam style? Would it hold the weight or eventually damage the bumper? I've read a lot about not adding anything to the bumper, especially while towing, but what about if not towing with it? I don't want to get anything welded to the frame, so if this won't work, I'll probably give up on the idea. Does anybody know for sure if it will or will not work with my RV? Thanks!
2015 38' Lacrosse 330RST Travel Trailer
2014 Ford F-150 4x4, with Ecoboost and Max Towing