Traveling from MN to AZ. Looking for advice or tips.

I'll be traveling later in Feb. with my family to AZ and I'm thinking to have my CCW tag along for the ride since AZ has reciprocity with MN(resident carry permit issued). I'm flying with Delta. I've done a fair amount of "Google'ing" for general tips/advice but hoping for folks who may have gone from MN>AZ and through Delta within this past year.So far I understand the following:The weapon must be unloaded and in a locked case. Ammo can be stored in the same case but must be secured in a box.I don't need to use TSA locks on the case.(?)I must declare my weapon at the ticket counter. I read somewhere that it's "helpful to notify TSA before getting to the counter". Has anyone done this before and how would I go about doing that?Since it's a handgun, can I declare it at the counter, get approval and then place it in my checked bag? Or will it travel separate and be a separate pickup after landing? (I've done a little more searching on this and it sounds like standard practice for Delta is to place it inside of your check bag. But that bag will likely need to be picked up at Baggage services with ID.)Any major law differences between MN and AZ? Planning to carry concealed as I always do. I'm going to do my own homework as well on this, not just rely on comments here. But if there's anything that jumps out or a super-specific thing, it would be much appreciated to get a heads up.Edit before i actually post: This link provides a good bit of clarification actually - https://ift.tt/1jk1bIU via /r/CCW https://ift.tt/302XOfH