Wow, that is some serious distance. Good luck, and let us know how things are going/have gone.
Longest walk I've done is 25 miles on hilly/mountainous terrain, the trail covering Scafell Pike, the highest mountain in England (which admittedly, is only about 3,000 - 3,500 feet) - this included about 30 minutes of canoeing over a lake too, so it wasn't all walked. Obviously, there were rest stops too. I'm not particularly in peak shape (I am slim and puny, and I live on junk food) so it was a real challenge for me. I have a great respect for people who push themselves with much bigger feats like the one you have planned. Again, best of luck!
It is not a trail. I am just walking from Anchorage to Homer. I am going to follow the Seward Highway until it connects with the Sterling Highway and then I am going to just follow it south.
I am going to start conditioning for the trip soon.
I looked it up on Google Maps and it looks like you will have a little bit of everything, terrain wise. It also looks like it will be a very scenic trip.
A few 50 mile walks to a town down the road (when I was younger) and 75 mile hike to class when I could not catch a ride ( yes I put my thumb out in those days)
Nowadays its across the street to get food. ( I walk enough all night at work)