You are right, that is an original part and needs to be there to keep the bedsides tight against the front bed panel when hauling a load. I would not recommend assembling the bed without it, even though you may not be carrying any loads in the future. All thread will work for replacement or we have a regular steel rod with threads on each end http://www.mar-k.com/front_bed_panels.pdf part number 110655.

Mar-Ktech