On the application, there will be three number codes for job choices -- one of them is ride op, another is any job in Park Operations, and then lots of others, of course. What worked for me to get where I want is I called them about 10 days after I sent my application, and then talked to whomever and told them where I wanted to be. Since I called and sent my application in early enough, it wasn't a problem! Good luck!
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Disaster Transport '97 Crew
Iron Dragon '98 Crew