Help... Vin #'s dont match

The VIN stamp on the package tray wouldn't be there if there was one stamped in the trunk gutter, it's an either/or situation, not both. Typically, Darts/Scamps/Valiant's were stamped in the trunk gutter, Dusters/Demons/Dart Sports were stamped on the package tray. Typically. Yours is not the first VIN stamp on a Duster/Dart Sport that I've seen in the trunk gutter, there's some speculation that one of the factories did it differently. Or maybe that guy at that factory that year didn't like stamping package trays for some reason. Who knows. But it would have either a partial VIN stamp on the package tray OR the trunk gutter.

The number in the middle of the package tray is just a part number for the package tray, pretty much all the sheetmetal parts have a part number stamped on them somewhere. The VIN stamp is normally near the driver's side rear speaker, on the rearward side. Or in that general area for fold down seat cars (no speaker hole).