Your "trusted friend" should have gotten the vin when he purchased the engine. It would have helped? you with your inquiry. If you had cross referenced parts for the 3.8L SC on Rock Auto you would have found that pistons, rings, rod brgs., long block, and crankshaft ALL FIT THE ENGINE from 1997-2007. Also the long block and the crankshaft fit 1997-2007 and the O/H gasket set and the camshaft fit the 2000-2003. Supercharger: 1998-2003. There are two places on the block that may/maynot have some numbers on the block but it is a 3.8L S/C built prior to 2004. see article below.
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