Gillette Slim: Adjustment Dial Setting Questions

My 1962 Slim should be arriving this week. I do have a few quick questions as this will be my first adjustable:

I've read that you should not adjust the dial setting with the solo doors closed. Shall I assume you should open the silo doors completely before adjusting the dial setting?

I've also read that you should turn the knob an additional 1/4 turn to lock down the blade. How do you know you are not over torquing it?

you can just untighten by a full turn before adjusting. you just dont want it locked down and put pressure against the mechanism. no 'additional' turning to lock the blade, just turn it all the way till it stops turning. no need to over tighten, just use two fingers till its snug

Thank you.

I agree with DanInFla. Backing off on the tensioning mechanism, which will be quite obvious by feel, is what I do on my 50+ year old vintage Gillette adjustables before making any adjustments. Some say it's important; others say it's not. In my mind, readjusting any mechanism while it's under spring tension makes less sense than releasing the tension first if you expect the mechanism to function the same way for the next 50 years!