My 72 CSi 4-speed gearbox has finally become much too loud. Louder than the engine (well almost). So now I am looking at getting a 5 speed conversion I always wanted. I may have access to a 635CSi (not sure of year) xmission rear drive and engine all for about $3500. Everything is overhauled I believe. I am not sure I want to do anything with the engine I may sell it separate. But will the drive system go in my CSi with one of these after market kits? If I don't get the 635CSi gear what are some good options in the aftermarket arena? I have looked at websites for Metric Mechanic ($3000 for conversion kit) and Korman. Thanks for any advice Chris