My buddy has an 02 with an NV4500. We are in the middle of installing a 3600 SBC sprung hub dual disc clutch. Pulled the input shaft out with no issues and slid the new one on but now we are wondering what this piece is for. I'm including a picture of it. It comes with 3, 12pt bolts that are around an 1 1/2" long. Please help ASAP as it's getting ready to rain and we wanna get the tranny buttoned up before that happens. Thanks.