Got my KP-15 specific lower parts in, that I ordered from KE Arms. The special extra wide (or long? whatever) hammer pin is 1.1 inches, in case anyone gets one of these and wants to look for an anti-rotation option (I might in the future).

The special safety selector appear to be just an ordinary milspec safety, with a 45 degree bevel milled or ground into it as shown below. I think the purpose is to allow the safety to be pushed out if the selector is turned to 45 degrees, according to the instructions.

I may try to put mine together next weekend if I get the time.

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