I'm not a smith, but have taken apart many different types of weapons, and reassembled them to functioning condition. USMC taught me decades ago to disassemble and lay the parts out in order, reassemble from last part removed to first part removed. that's worked for years, and still does.
A well known coating company is telling me I'm doing it wrong. LOL the manual I have, and the method i've used on dozens of AR lowers have worked, it's even worked with the well known coating company's parts on 3 other builds. here is my order of assembly, you decide if iI'm losing it or not;
1. install mag release
2. install bolt catch
3. install pivot pin
4. install trigger/disconnector
5. install hammer and cock it
6. install safety selector and grip, test for function
7. install buffer extension, take down pin and stock of choice
that's worked dozens of times.
latest attempt using a Mega Arms lower using the above method FAILED at the install safety selector, the trigger platform is peaking above the holes the safety installs into. tried 2 different safety selectors,,,ZERO success. checked my work,,,spings in correctly, everything lining up but the safety still won't go. Install an Anderson stainless trigger,,,,voila! all is well.
The well known coating compay tells me I'm doing it wrong, I should install them in this order, trigger/safety selector/hammer. I tell them I tried that but the weapon fails the charge with trigger held back, release/clunk test,,,i.e. it fires. Still my mistake tho, according to them.
Fool me once, shame on you. Fool me twice, shame on me. Even tho I really like their bolt carriers they'll never get another penny from me. In short, they have FAILED miserably in the CS portion of the business in addition to shipping a dicey trigger/hammer assembly