This is typical! I was having my boat serviced and asked them to put an outdrive lock on for me. If you are familiar, they just unscrew one nut and screw on the lock. About a 2 minute job. They charged me a half hour labor, around $40. I asked why it was so expensive to install considering I was doing my other services in their shop. The service manger told me they had to tap the threads for it to fit. I walked out to the garage when the service manager wasn't looking and asked the mechanic who worked on my boat if he had to tap the threads. He said no and confirmed it just screwed right on. Needless to say, they would not take the labor for that off the bill.
