stock rear end size and gears in a 92 5.0

More than likely it's a 3.08 gears...maybe 3.27s...

The 5.0s had the 8.8 rear end for sure.

Check your sticker on the door'll have the code for the axle on there. Post the code, and assuming that the gears are still stock (likely) then, that will tell you exactly what you have.