Hope for the best, but plan for the worst.
What does "everything" include? If you're selling a house that you've owned for a long time, you will never again be able to buy a house if you blow all the proceeds on traveling around. (I think you'd also be liable for extra income taxes if you didn't buy another house with the money in a certain amount of time, but check with your accountant on that.) So where would you live if you couldn't travel anymore?
What will "selling everything" net you? If it's only $50,000, heck no put your money in the bank and stay home, travel on weekends. If it's $5 million, well, put a fifth in savings and have fun! If it's somewhere in between, count the cost as someone once said.
If a semi smashed into you, or one of you tripped over a stump and broke a vertebra, or had a heart attack (which happens to plenty of strong, healthy people unexpectedly after 60), or came down with a bad case of tick fever or Lyme disease, or for any reason needed lots of medical/nursing care and expensive pharmaceuticals, and the other had to take care of the sick one full time -- what would you do?
Have you got close, loving, financially independent children who in the worst case scenario would look after you and either take you in or make sure you had decent accommodation, utilities, food, medical care?
I know of lots of folks over 60 who have bought a Winnebago or whatever and toured around the country - but they still kept their house and had somewhere to come home to when the road got too tiresome.
I wouldn't recommend any couple at your age hitting the road without first having two or three years' complete living expenses locked away in a savings account or very very very safe investment.
But then - as you said you only live once. You can do anything you want to do - as long as you're willing to take the consequences.