Good morning. I just acquired an old 35 hp mercury and need some help finding parts for it. I think it about a 1986 model but not sure. The serial number on the tag is A951810 but when I put that in on the mercury parts search it says serial number not found. Is the motor just too old to look up parts like that or am I missing some numbers or letters? Tag looks fine and clear and that is all that is on it that i see. How can I look up parts otherwise? Thanks.