pull the tank...
Not quite as easy as some have stated, but still not a bad job. Need to get the back end up about a foot higher than the car usually sits. Also have to disconnect the fuel inlet hose to the tank.
I tried the 'cut an access hole' on my 2001 Blazer (not a TB, but similar arrangement) to replace the pump that way. The problem comes in trying to remove the fuel pump locking ring. Most likely it will be rusted in place and you may have cut/bend/break the old one to get it off, so buy a new ring when you get the pump. You will need working room to do this.
*my new fuel pump did NOT come with new nylon locks for the hose connector. Buy some of those also.*
Then you will want to clean up the area around the mount ring and lastly the new locking ring takes some force to get it in place.
All of this is a lot easier with the tank on the ground....
Probably a good time to replace the fuel filter also, and remember to reconnect ALL the fuel lines. (ask me how I know...)