Natural gas is wonderful and super simple to add a stub and valve.
Here is a video of a National3A on natural gas.
https://www.youtube.com/watch?v=lBjocpE-FxE
A Bethlehem Alpha.
https://www.youtube.com/watch?v=x7uBTg5Zd04
The gas is easy to hook up, you just find the dirt trap in the line and add to it from there with a new dirt trap.
I think its worth doing for any of the 6-7 jet torches. It will not run a GTT Lynx though.