By far and away, the hardest part of replacing your waterpump is removing the old bolts and studs WITHOUT SNAPPING them off below the timing cover. Do a search on this forum for snapped waterpump bolts or accessory studs and you can read about the horror first hand. Snapping a bolt/stud will add another 4-5 hours to the job if it breaks behind the timing cover. Do yourself a favor and buy some PB Blaster and soak those bolts every chance you get. Heating the areas around the bolts with a propane torch will also help in the removal process. Whatever you do, DON'T USE AN IMPACT GUN to remove any of bolts and studs. Just try and apply force in a "back & forth/ up & down motion. Try not to over exert too much steady pressure with a breaker bar in any one direction. The key is slow repetitive back & forth motions. I highly recommend replacing the bolts and studs. You can buy all replacement grade 8 bolts at Lowes for short money. Here's the link for the accessory stud kit:
http://www.partsamerica.com/ProductDetail.aspx?mfrcode=RNB&mfrpartnumber=23744
Each kit only comes with one long stud, so you need to purchase two kits to get 2 of the longer studs for replacement. Use plenty of anti-seize on all bolts and studs in case you have to replace the waterpump in the future.