Fuel Stabilizer

I put away my 1996 Polaris SLT 700 in the garage with a half full tank
of gasoline last fall. I poured some STP stabilizer ( the red stuff)
into the fuel tank. In previous years, I did the same thing and later
in the new season I added some fresh gas . I was always able to start
it. It was not run this summer and will stay in storage another year.
Should I add more fuel
stabilizer ? Fill the tank with fresh gas ? What should I do ? Filling
it with gas and taking it for a ride is not an option.