Serpentine belts are easy. I remember doing mine right after I bought my Z when it had 62k. When I had my mechanic look at it before buying it he said that it needed a belt, so I replaced it. On LS1s there are two belts, one for the water pump, alternator, and power steering, and another for the a/c compressor. I only replaced my power steering/alternator/water pump one and it was easy. Just use a 3/8" (I think thats the size, but you can use trial and error) ratchet on the tensioner to slip the belt off the pulley and pulled it out. I then looked at the diagram on my driver's side strut tower to see the route for which the belt follows, and reinstalled with the last step being the belt tensioner (I used the ratchet to take the tension off, and slipped the belt off). You will need to jack your car up for this, and possibly remove your intake tube to get at it better (i dont remember that part but I might have had to). Its really easy, should take no more than 1/2 hour. Good luck.