The battery tray on my trailer broke this summer after countless miles of washboard and bad forest service roads. I have a friend who runs a welding shop. I took the trailer over and we fab'ed up a new tray and welding it in place of the old tray. I drilled a few holes and threaded some all thread bolts through and remounted my batteries. Of I did prime and paint the whole assembly. It was only a few dollars of materials. Mostly from his scrap pile. It took one of his employees about 30 minutes to put it together for me. It's just big enough to hold two deep cycle batteries. It's mounted just above the spare tire on the front wall of the trailer. Look at your trailer, determine if it's Aluminum or Steel in the area where you will mount the batteries and find a metal shop that has the proper skills to weld on that type of metal. | 
Mounting batteries on a gooseneck trailer
