hey chuckp first of all welcome to the board!
you can go up to the top of the page and do a search for alot of the questions you have. they have been discussed highly on this forum.
after that is said....
no you don't have to move the firewall. you just have to beat the lip back, so the tranny will clear.
you will have to do some cutting for a larger radiator, because the stocker will not cool it effectively.
hooker makes motor mounts, or you can fabricate your own.
jegs sells the motor mounts and headers if you so desire.
here in the information section of the website is budget V8 swap info.
http://www.luvtruck.com/pdf/engswap.pdf
also you can go into the pictures section and spend some time looking at peoples setups to get ideas on what you want to do to your truck.
hope your visits to luvtruck are pleasant!