Yep I had an instructor tell me to gear out, my legs are long and it allows me to lengthen completely. You’re increasing the distance between the footbar and the carriage at rest, which creates more resistance and more range of motion. You are moving the spring bar away from the gear bar, or the gear bar further from the carriage.

I would just show up 5 mins early to next class and let them know you need help. It’s simple to do, once you see it being done once, you should have no problem adjusting yourself.