Several things seem a little strange, 1) Where is the requirement for the hot/cold bonding within the first 5'? 2) Is the 18" measurement the exposed conductors out of the weatherhead? My POCO wants 3', but the connection crews sometime cut them down to 1'. If this is your case why would you need to measure. I would think that as long as you were close to the 18" it would be no big deal. I certainly wouldn't climb up there just to measure.
