"Grey Wolf", as stated, most sway controls come with the appropriate mounting hardware: bolts. Today's frames on RV's are made from steel alloys for their "strength/weight" ratio. This said, mounting a sway control by using the supplied mounting bolts is the appropriate way. Welding on any frame components is not a good idea. The heat from a welding process can/will alter the metallurgy of the frame metal which can/will leak to premature cracking. A lot/most of the newer pick-up trucks have stickers on the frames for this same reason.