150 XP has bent prop shaft and leaks gear oil after hitting debris. I took it to a local mechanic and he told me the second snap ring broke and he couldn't take the unit apart and I must by a new l/u. Seems strange to me that a busted snap ring means I must buy his new lower unit. I ran the boat about 15 minutes back to the dock after the hit, but the unit was filled with a 50/50 mix of water and oil. Thought I'd run this by the pros before I shell out 2 grand or spend a few weekends takeing things apart. The motor is missing the serial tag but is somewhere between an 84 and 89(any other way to tell the year). Any ideas or suggestions are greatly appreciated.<br /><br />Thanks in advance<br />Dave