I just bought a 17' boat with what I thought was a 75 HP Mercury motor. I have been unable to determine what year the motor is. Upon investigation I found that it was an in-line 4 cyl. The only serial number I have found is on the lower unit, it is 6613694. I also found a model number which is 1075525. What do I have or where can I find out. The website that I've seen posted for serial number identification is all written in Swedish. Thanks