A progressing cavity rod-driven well pump utilizes a tag shoulder above a helical passage of the stator. The pump stator is located at the lower end of a string of tubing. The tag shoulder is more restrictive than a passage through the tubing. A pump rotor is secured to a string of rods and has a stop located above the rotor. The rotor is lowered on the rods until the stop lands on the tag shoulder. Then the operator lifts the rods and the rotor to accommodate for expected stretch during operation. By removing the rods and rotor, monitoring tools can be lowered through the tag shoulder and stator.