Originally Posted by Danjo
That’s good stuff.
8” high channel, 12 gauge, maybe but no welding.
In general, a bending beam is under compression on the top, tension on the bottom, and unstressed in the middle (in a chassis beam these roles alternate as the beams flex while driving, but the middle remains largely unstressed). A general guideline is to keep drilled holes in the middle third of the web, so a 2" to 2.5" hole to accommodate your 1.5" brain pipe in an 8" channel should be fine. I wouldn't do it myself, though, if I could find any alternative - like having a smaller brain.