Tractor Repair: how to change a belt on 42 19.5 hp sears automatic, drive shaft, lawn garden

Question
Hi,
I have taken this machine to a repair shop, but as soon as I used it the belt tore again. I'd like to learn how to change it myself so that I might be able to troubleshoot this problem. It has a drive shaft and two decks. There's a center pulley and I seem to recall at one time that there were two belts. Now there are none. Can you help me, I've missplaced the manual?

Answer
Hi Britt
  I  am not the least bit familiar with the Sears lawn & garden line of tractors. If you will go to this site & post your problem on this forum I am sure someone will be able to help you with your problem. There are some pretty sharp people answer the post on that forum Hope this help you some Big Dean
  http://www.ytmag.com/gardent/wwwboard1.html