Just looking at the topical map between my ears, I think that to get where you want to go you will need to go around or over a mountain range.
I have never drove a MH for any distance, but back in mid '70s I would run KC to Searcy Ak with a naturedly aspirated NTC 250 Cummins a couple times a month. I found that I could make the trip easier running 60 to 63 and down than I could on 65. Now over the decades they have done a lot of work on 65 moving it around towns, straighten the curves, making much of it limited access, and reducing the dips so you go up/down at a more constant rate.
2009, I hauled a permit load south on 63. Now 53 ft RGN load 10 ft wide, GVW near 98,000. That short section of 63 worked me pretty hard. Few weeks later, moved the machine again. This time the permit called for me to come up 65. That improved road gave driver a lot more room for mistakes, but my transmission and rearends got as hot south of Branson as they did when I took same machine thru Eisenhower tunnel.
All this is a lot of words to say I think 63-60 is best way. After all, the only hard part is less than 30 miles long. Any other route adds more than 30 miles, so if you drive that section at half speed you save time.