If you are removing the old angle by drilling the spot welds, you will have a row of holes along the bedside anyway. We suggest plug welding the new angle on through the drilled holes then grinding the welds smooth on the outside.
http://www.mar-k.com/Catalog/PDF/Instructions/37-53_Angle_Strips.pdf Whatever the method, know that the angle is an integral structural part of the bed assembly and should be securely attached. That may be less critical for a 1-ton since the cross sills are attached to the bedside stakepockets. Good luck with your project.
Mar-Ktech