How close can an IMC coupler be to the unsupported portion of the rise above a roof?
Some great suggestions and I did get a shorter 5' piece of the 2 1/2&quot; IMC threaded and did exactly what Freeman and Ecnerwal suggested.  But to answer my original question:

Answer: The final top section of IMC conduit needs to be securely tied to the structure by at least one strap/tie. (This is from my interpretation of my local codes and discussions with the TEP installation engineer) This means the coupler will need to be (at least) ~6&quot; below the top depending on the wall makeup you will be tying to. (more is better).  And that a second strap/tie will need to be BELOW the top coupler more than 8&quot; (from the TEP SR guidance).  So from what I've found and interpreted, I  Could have set it up like my original cartoon, but the recommended way was superior and had a stronger finished &quot;appearance&quot;.    This is my interpretation from my local electric company service requirements: https://esr.tep.com/wp-content/uploads/SR-305.pdf