Pretty much that simple. Big blocks have a fuel pump pushrod that runs off of a cam eccentric. You need to make sure that pump pushrod is pushed back up towards the cam before you slide the new fuel pump arm in place. The fuel pump pushrod should not be able to fall out. It will only drop down so far, and stop. If for whatever reason you did need to take it out and replace it, there is an allen plug in the motor, right below the fuel pump hole. You can take that plug out and the fuel pump pushrod will slide right out. This will all make more sense when you're standing there looking at it. Good luck.
