I have a 7.5 Mercury 1983. When I replaced the impeller, the drive shaft did not align correctly. Now my neutral is closer to the reverse on shifter and I end up starting the engine while in foward gear. And my reverse does'nt work. Can you tell me how I can align the lower unit in order for gear to be correct on shifter? Not very convenient starting in foward and unable to go reverse. Thank you for any help offered.<br /><br />Drobles83