Small Engines (Lawn Mowers, etc.): drive belt, rear fender, mtd

Question
I need to know exactly how to replace the drive belt on a 1987 or 88 300 Series Agway ride-on lawn mower. I can't figure out exactly where it goes because the first one snapped off so I didn't see where it went. Do you have some kind of diagram or can you refer me to someplace I could find one? This would be much appreciated, as my back yard is becoming a jungle. Thanks.

Answer
I am guessing you mower was manufactured by MTD or Murray.  Are there any stickers on the rear of the mower identifying a model number?  The may be under the seat or rear fender.

Please look for and send me the model number so I can look up some information.
Eric