Project Cheap & Nasty Updated With Back Story

That’s a good thing. Wastegated turbos are junk. They’re better suited to lowish hp oe stuff. You actually want a stand alone wastegate. It lets you set the priority and choose the sizing. Most internally gated turbos have tiny gates.
How do I put one on this? Get a complete wastegate exhaust turbine housing? Seems simple enough unless there's another way.