If you have the cap off, leave the pipe alone, just screw the shower head onto it.
If you can post a picture of it here taken from about 8 feet away that will help me be sure of what you have, use the paper clip icon at the right end of the tool bar above, or the 'attach files' link to the left of your send button
We can go from there, If I miss you tonight I will pick your response up in the morning,
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