@RoryTheFerret , Yes I do have BOTH the metal plates or metal gaskets that came with the cast iron tensioners. I could not use them because the oil passageway hole in the metal plates did not align with the oil passageway in the engine block. Also, they are fairly thick - maybe .060 to .070", and without them, the tensioner plunger aligned perfectly with the matching slot in the back of the metal tensioner arms that I got from Modular Motorsports Racing. If you need the plates, let me know.
My truck is running / sounding / performing absolutely beautifully. So I guess they are doing their part like they are supposed to. I'm sure I wouldn't do anything different if I had to do it over.