On your L angle cutting question. Just use straight snips, then clean up with a fine file. The best thing to have if you don't have it yet, is to get the emory wheel for your bend grinder. You have to learn how to use it so it doesn't throw parts at you or bend them, but once you get the hang of it, it will debur or smooth up manageable parts really fast. Like a scotch brite deburring wheel.
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