Does anyone know the correct john deere l120 pto clutch OEM part number?

[Kim Dean]

I tried search and am looking for a john deere pto clutch for my john deere l120 riding mower.
According to this blog,Electric Clutch Buying Guide , Finding the clutch part number located on the clutch makes the proper selection of a PTO clutch a simple task.
But the bad john deere l120 clutch was too old and I can't seem to figure out which the correct part number is. Can anyone confirm what is part number? Ideally it would be the cheaper if I buy aftermarket pto clutch, right ?

 

[Zebrafive]

The JD P/N is GY20878 $150.00