If I understand?
Fastest, strongest:
Cut on horz bandsaw, fine tooth blade (thickness unimportant), use coolant, low RPM. Harbor Freight has cheap models ($200), so do many of your buddies. You can set the 7.5° (per side) at the saw vice which is built-in.
Blow off, clean on wire wheel. Weld 100% around, using a jig (c-clamps to blocks OK). Bending steel near a saw cut isn't optimal. It's weaker, and can start cracks, and you aren't saving any time or money anyhow.