The way that example script works is that it takes the analog input connected to channel 1 of the Maestro, which is read as a value between 0 and 1023, and maps it to a target value (in quarter-microseconds) from 4000 to 8092. There are a few ways to reverse the extremes of the servo (so that 0 corresponds to 8092 and 1023 corresponds to 4000). One way would be to change the line of code that maps the target value (
4 times 4000 plus) to something like:
4 times 8092 swap minus
This modified code should effectively multiply the input value by 4, then subtract it from 8092, resulting in target values between 8092 and 4000 as the input changes from 0 to 1023.
By the way, it sounds like you might be using this to control a full-sized, ride-on go kart. If that is the case, please note that we do not recommend our products be used in projects where failure can lead to injury or property damage.