How to make your Water Heater adjustable for $8.97

1.If the high cutoff is 180 on factory tstat, then the low at 140 is what the water heats to and the 180 is strickly for safety! Is that right?

2. if you wanted the water to be hotter say 170, then the adjustable would allow this and the 180 factory would not engage...this seems a silly question but is for clarification?

3. if I read this right you have bypassed and subed the adjustable for the 140 low cutoff from factory...right?

Thx for your answers. Hope your weekend is going well.