Right now I AM ENVIOUS!
But happy for you. The reason I am envious is my truck is torn down to the frame right now.
Much like you, once I get the truck back together the plan is to head west. Two years ago my wife and I took the Harley out to Sacramento on US50! Talk about an EPIC trip! Next time it will be in the '68 SW! I cannot wait.
We haven't been down south like you are planning but my plan is to do that someday.
I hope you will take pictures along the way and share them with us. Safe travels along the way!