Steve, Any later model 5 speed gearbox from an E12 or e28 will fit(upto 88 I believe) directly to your existing belhousing. Things to note though...: 80-81 E12 boxes have provision for the speedo cable(you'll need a longer one), 82 and later... you will need to install the speedo drive gear, you WILL need to get a 5 speed driveshaft also. Sean BTW: check out www.firstfives.org