The oil dipstick tubing is only one piece, there is no other parts. I saw a ford engine being rebuilt before, the mechanic put a grease at the bottom part of the tube and he just push the tube little by little inside the hole of the engine block. He was holding the tube more on the bottom part. Then, he bolted the bracket on the top of the tube so it would not move.
Unless you broke the bottom part and left some part of the tube inside the hole of the engine block. Now, that is hard to fix.