Can't make Servo Output min trim max work

Hi. I’m building my RC boat and need to change min and trim values for 3 position switch. Now is by deault
min = 1000
trim =1500
max =2000

I need to change it to

min = 800
trim =1000
max =2000

In the Servo Output section I set these values, wrote params into FC, but nothing changed:


Does it actually work?

P.S. I user ArduRover for my RC boat

Input does not scale. You have to change it in your remote.
Max min values are for scaling servo outputs.