Key differences on our AR15 as you read through the articles: Note that when they discuss the Bolt Catch assembly in these articles, our system uses the stainless steal dowel pin and set screw rather than a roll pin that comes with most Lower Parts Kits. Just ignore thse sections that don't apply. Install the spring and mag catch buffer pin, but use our stainless pin to hold the mag catch in place, then hold the stainless dowel pin in place by screwing the small black set screw into place. You'll have to use a little bit of force to get the set screw going.
On the AR15 Lower and our 308 Lower, we also use a square nut and philips screw to install the pistol grip rather than the screw and washer provided in most Lower Parts Kits.
|AR15.com Article: How to assemble an AR15||(Click Here)|
|Brownells Videos: How to assemble an AR15|
(The most applicable sections are Upper and Lower Receiver
installs, Handguard and Muzzle Break installation)
|TheNewRifleMan.com Article: How to Build an AR15|
(Lots of detailed pictures in this one)