Thank you! Incidentally, the Pentax K1000 is the only other Pentax with the same type of "light switch" as I call it. The stop-down lever should be the same as the ES and ES II models.
Many people got confused with that lever, including me when I first got one. I was used to the SP and SP II and had a couple of rolls badly exposed because I was flicking the switch up whit the SMCT lenses. Didn't read the manual until it was too late!