I have determined that my heater core is bad. My truck is leaking antifreeze, I have a thin film covering my windshield, and it smells like antifreez in my truck. I plan to replace the heater core my self. After some research I found it is difficult and time consuming to access the heater core. Does anyone have any advice, instructions, or documentation that would help me replace the heater core? During the process are there any tricks/tips, any special tools or any major problems I should watch for? Any suggestions are welcomed and will be helpful. Please let me know what you think. Thanks!

Its not as difficult as it may seem to change the core. My best advice is to go to AutoZone and pick up a manual.
I have the Chilton Manual and highly recommend it, but, Haynes is as good and should contain the info you need.