Believe your post shows you have a 383. When you remove the fuel pump in a big block, the push rod will likely drop down as it comes in contact with the arm of the pump. It's a bit tricky to get it pushed back up and keep in position so you can install the pump. Usually a thick coating of a heavy grease on the rod will keep it in the up position so it won't be fighting you to get the pump installed. If I remember correctly, the rod should be 3.25" long, but you may want to double check that number.