What gauge are the bed rails?

What gauge are the stock deck rails? I need mounting points for my new headache rack further toward the front than the stock rails allow so I'm thinking about replacing my stock rails with superstrut. The 1-5/8 x 13/16 strut that I'd like to use is 14 gauge. The next size 12 gauge strut is 1-5/8 square but I'd rather not use it as a replacement. However, Taco2022 has a superstrut system for his bed rack that he mounts on top of the side rails that I might use as an alternative.

https://www.tacomaworld.com/threads/bed-rack-hack.636774/