Welcome to the Moms Panel, Annette! I see you are dining at
Chef Mickey's soon. I have to admit; I'm a total sucker for those Tater Bite Potatoes and the Create-Your-Own Waffle Bar!
I've been thinking about your question, and here are my thoughts about making it to your 7:20 am Advanced Dining Reservation. The parking lot for Magic Kingdom Park is at The Transportation and Ticket Center (also referred to as the TTC), and this serves as the hub for both
Monorail lines. The Express Monorail will start running 30 minutes before park opening, so in March this means 8:30 am. Instead, you'll need to take the Resort Monorail, to
Disney's Contemporary Resort, which currently starts running at 7:00 am. However, there is no Monorail schedule posted online, so I'd advise you to call Guest Services at 407-824-2222 a couple of weeks before your trip. I also worry that this still may be not get you to the resort on time. You may want to consider parking at the hotel since it is complimentary to park there while dining (they have
valet parking for a fee if you'd like to park there all day).
Also, Uber and Lyft ride-sharing services have become very popular with Walt Disney World guests staying off property (I used it last year, and it was effortless).
Hope this helps, Annette, and don't forget to wave your napkin in the air when you see Chef Mickey!
Eean