what year and model tractor do i have,

[Soundguy]

he's given us virtually no info to go on.

if the ring gear wore out.. I';d expect pinion to have worn out too.. but ring gear may hav ebroke.. and pinion fine.

while in an auto i'd replace as a matched set.. in a tractor.. if one or the other ;looked good,, i wouldn't beat myself up about piecing it.

still.. we need more info...

soundguy

 

[RickB]

All US-built Fords prior to 1965 use the same starter ring gear, part number 9N6384. Based on the numbers you provided, if the fuel tank sits EXACTLY over the top of a 4 cylinder OHV engine, that's what you need. If it is a three cylinder engine, that ring gear won't work, and there are different ring gears for gas and diesel engines.
I'll ask again, which side of the engine is the starter on?

My bad; the OP wrote ring gear & spider gears, I READ starter ring gear. MUCH more info needed to help him out.

 

[COASTBUSTER]

what side of the tractor is the starter on when sitting on the tractor

the starter is on the left.

 

[whodat526]

the starter is on the left.

you have a pre65 model then which is the same rear diff as a 800 series and 850 series