I had old fuel problems with my 79 till I started using Stabil.
BUT
It holds 30 gallons and the truck is driven about 40 miles…a year !
You’ll have to do your math on this one to see if you’re using up the fuel in the tank in a year’s time.
If not, use Stabil.
Hard starting, running rough ? old fuel.
Sniff it, it should smell like gasoline. Old gas doesn’t smell right, you can tell.