21 spline input shaft; California Residents: WARNING This adapter assembly includes a new Dana 300 input shaft with 27 spline and replaces the existing stock Dana 300 input shaft. The GM 4L60E / 4L65E adapter to the Jeep Dana 300 is 4.00 inch in length. And the overall length of the transmission and adapter is 25.875 inch. Adapter material is 356 T-6 heat treated aluminum alloy. The adapter has a provision for a transmission mount. The adapter kit includes an adapter housing, adapter ring, new Dana 300 input shaft with 27 splines, GM VSS sensor, reluctor ring, O-ring, gasket, fastening hardware, and adapter instructions. Transfer Case: Jeep Dana 300. Transmission: GM 4L60E Late Model (1997-2007).