I have gotten mixed responses from folks on the phone at ATF on this issue. Some have told me I need my name engraved with location and others on the phone have told me that if I'm converting an already manufactured lower to an SBR that is already marked with a mfg and location then all that has to be registered is the original serial number. One individual actually told me that if I was manufacturing that I would have to submit plans specs and pictures of the lower. I took that to mean from a rough casting.....he was very short on the phone. Seems to be what I run into every time I talk to someone. And it seems that every time I question them,the response I get is "this is how it needs to be done" which of course is the way they tell me. Then I read the internet and get conflicting info and call back with another different response and attitude. My hope is that we don't have to engrave anything.