Hello C.,
Welcome to the forum.
Whenever you post about a machine you are working on, we need the product label information off the machine. Usually, it is under the seat or on the seat base.
For anything engine related, we would need the numbers off of the engine itself. The engines are only supplied to the final assembly plant.
Craftsman is a private label box store brand name. These mowers are actually made by MTD, and earlier models were even made by Husqvarna
From the description of the problem, it has locked up a tensioner idler or stationary idle pulley for the drive belt.
The instruction label you asked about is basically how to set the pedal to maintain a constant set mowing speed aka as cruise control"
