Well, let’s see... subsection 3:
So, this says that any and all firearms made without a serial number after 1968 are illegal unless you get a SN from an FFL, affix it within 10 days and then bring it to the dealer to show proof of same. Sounds legit.
In addition, it makes illegal to advertise for parts kits and also to purchase and own them, effectively making it impossible to build your own. This then makes the basic law requiring serial numbers just a way to confiscate those already existing out there.
Even an FFL cannot build an AR, semi pistol, rifle or shotgun unless he also becomes a manufacturer.