Thanks for the update.
Just keep her well oiled and sufficient coolant and I expect it will get you home just fine.
You're in my prayers to make a adventurous and safe trip home. Yep.
Best,
Charlie

BTW: Give us a post when you get back.
BTW: The popping out of gear will likely increase in frequency. Is the gears fully meshed or is the linkage off a bit. I would investigate the before starting back. I had a 41 conv. doing that to me on the way from NC to Erie,Pa way back when. Got to where it wouldn't and couldn't be held in drive. Then second started doing the same thing. Ended up having to leave it in western PA. Got back from Erie and guy I left it with helped me pull the transmission and fix it good enough to get back to NC. Talk about adventure, I have had some with my old 41s.