I need help with my Muncie transmission. 1969 Corvette 350, Muncie M20 4 speed. All components are STOCK. The gear shift and linkage are STOCK, NOT Hurst. I had the trans rebuilt, put it back in, but I can't get it to shift through the gears. It will only go into 1st and I hit a brick wall when I try to shift into 2nd, 3rd, and 4th. I did align the shift levers in neutral before bolting them down. I have no idea where to go from here. ANY help would be greatly appreciated. Thanks.