Hello G.,
Welcome to the forum.
What we need more than a year model is the product information number (PIN) label information off of the chassis. The label in on the front side rail on some models, but many of them have the label hidden under the fender between the tire and frame.
John Deere often had production number changes due to updates.
With a lever type PTO operation, the belt must be correct, and the operator cable also has an adjustment down on the deck cable bracket. Often times an aftermarket belt causes this problem.