Tractor mis-adventure

What I learned today. Just because three point hitches on tractors are "universal", doesn't mean that all implements will fit without modification. We rented a tiller only to discover that the drive shaft was too long. It could have been easily modified, but since it was not our tiller we were out of luck. We didn't learn this until after we had struggled with it for several hours. Which brings to mind another important lesson I have learned. Ask for help.