Colt Case Ingersoll Garden Tractors

Take the tank fitting out and replace it with a tee fitting. Drill a couple of holes and some grommets and you can easily have an easy-to-read fuel gauge.

Picture!

Quite ingenious Steve! If I did that I'd consider a protective ss or copper or brass tube though, with a window cut for viewing.

This is basically how the boiler water level in a steam locomotive is checked.
I didn't realize the older tractors didn't have fuel gauges.