I figured out the parts from Shurflo years ago and have been rebuilding the pumps myself with zero issues and they put out 150 plus. As mentioned its 20 to 40 bucks in parts and very easy.
Disconnect wastegate and go WOT and see if you get KR. That will help pin point a posible machanical false KR like a loose something rattling against frame or block and knock sensor picking that up.
You can remove shaft by taking the screw out that holds down reluctor cup. With that said DO NOT USE FACTORY ROLL PIN!
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