cut 6 1/3 sections
cut 6 3" angle irons
weld 1 angle to one section
drill 3 1/8" holes in angle
align and drill 1/8" all remaining sections
align and drill 1/8" all remaining angles
drill and tap 1/4-20 all sections
drill all angles 1/4"
Assemble angles to sections
Align all components and weld remaining angle ends to sections