Here's my thinking:
The text of 922® states:
It shall be unlawful for any person to assemble from imported parts any semiautomatic rifle or any shotgun which is identical to any rifle or shotgun prohibited from importation under section 925 (d)(3) of this chapter as not being particularly suitable for or readily adaptable to sporting purposes
Since Mini-Bus now prohibits the DoJ from applying the sporting purposes test to shotguns, those shotguns previously affected by this section of law are no longer prohibited from importation. If the shotgun is not prohibited from import, then it is not illegal to assemble one, regardless of where the parts came from.
So is 922® repealed? No. As the sporting purposes test still applies to rifles, those firearms would still be affected. But shotguns, in my reasonable man opinion (I won't say legal opinion, as I'm not a lawyer), are ok.
