Neat link dude. That was an informative read. Appreciate it when people posts good resource links when posting.
Thanks, I actually was on the fence a few months ago about welding on the frame myself, so I did the research until I felt confident that it was acceptable.
It was during that research, both forum & technical documents came up. Most of the forums were people adamantly opposed to each other in the weld vs. no-weld camps. The technical documents were useful if you take the time to read & understand them.
I found a Ford document too, it mostly said it was OK to drill holes, but not within another 1" of existing and a few other common-sense things, all in keeping with what I found and linked above.
All this, coupled with the fact that I worked on Class 8 trucks (semi's) at my last job, and our 2021 Navistar trucks came from the factory with some cut/welded places on the frame, I figured it was OK, if you followed the recommended practices from various OEMs. They all had slightly different recommendations, but none of them were at odds with each other.