We have been to Alaska 8 times, twice driving our E15B. One trip up the Alaska Hwy to Homer and back on the Cassiar.
https://twohikers.smugmug.com/Alaska...htoAlaska2012/
On the second trip, we ferried to Skagway, and then drove from that point (and eventually back to Bozeman
https://twohikers.smugmug.com/Alaska...on-2017-Part2/ Even driving 40 miles up the Dempster in a rain storm will get you very muddy. But all that said, the front of the storage box really protects the lower front of the trailer. Another thing: sure, you will run into highway construction which will slow you down, but that keeps the rocks from flying. Probably some mud flaps on your TV will help, but just plan to spend some quality time at car washes. Have a great trip.