I put the Keisler TKO in a '70 Challenger. Originally auto. Prep was two steps. First was to put in a standard 4 speed hump. Next there is a tight place in the tunnel, especially on 70's manufactured in California. Keissler supplied an extra piece of sheet metal. I cut out a small section of the tunnel per instructions and welded in the extra piece to create more clearance. The trans fit perfectly and I was able to shim up the trans mount to dial the driveshaft angle right in.