I'm trying to get the correct fuel pump for my supposedly 1996 Volvo 4.3l sx. The part number off the existing one is 3850809. When I cross reference two numbers come up - 18-7326 and 18-7329. Besides these two choices the original part # is tied to 1993-94 4.3l but not 1996. Cross reference for 1996 indicates a high pressure fuel pump 3857650. My hull indicates a 1996 boat. What gives and what is the correct replacement. I didn't find an ID or SN on the engine. Could I have a 1994 engine in a 1996 boat? I bought it used several years ago.