Ordered a CA mod kit for my AR-10 i emailed them a...

Ordered a CA mod kit for my AR-10 i emailed them and they said it would fit my particular gun. I watched the how-to install video they told me to watch... Only problem is that the video on how to install this kit is way too vague and doesnt even show which way the rear take down pin goes in, or which side the spring goes on... I searched and searched, and finally found a phone number but it's just a recording saying they won't answer the phone. I was trying to go shooting but it takes them so long to respond back I had to cancel my shooting trip 3 times! I emsiled them stating that the video they provide on how to install their kit does NOT show which way to install the rear take down pin, or which side the spring goes on, and they just replied back with a link to the exact same crappy video that doesn't show how to install the rear take down pin(which direction to install it and which side to install the spring on?) So now I'm still waiting to hear back from them for an actual answer to my question, and I had to cancel my shooting plans again! Avoid this company unless you pay a gunsmith to install it, because the how-to install video is awful! I also heard that once you get it installed, you can no longer use Magpul Pmags, and your bolt carrier lock will no longer lock at all! Ok I figured out which way the pin goes, my AR 10 has a bottom mounted spring, mot a rear seat ounted one, now another problem! My LMT AR10 uses a hex screw instead of a roll pin so this kit won't work on my gun! I emailed them before I bought it and they said it would work on a LMT AR10! Now I'm out $75! They won't even answer their phones! What a horrible company!