The conventional wisdom that some others have is that "reasonable restrictions" such a licensing & permits are still allowed and that Heller/McDonald only prevents complete ban's such as Chicago/DC.
The 15th amendment gave blacks the right to vote. But states found a loophole by requiring a poll tax to vote, thereby preventing blacks from voting because at the time they were mostly poor. It took 94 years and the 24th amendment to close that loophole.
So based on that history a shall-issue gun permit is effectively just a gun tax. And it may be constitutional unless another amendment such as the 24th is passed that ban's any gun-tax or permit schemes.
I'd say McDonald/Heller will have no impact on MN currently.