Sorry for your troubles, I'm glad I talked myself out of not using the same upper and lower. I had a Aero ME5 lower and parts kit but was starting to get cheap looking at BCA uppers. Then I started reading on the problems because the AR-10's aren't mill spec. The good forum members here talked me out of it and I bought the Aero ME5 upper. It works flawless. Good luck, there is lots of knowledgeable folks on here.