Can you spot the oil pump in this picture? Hint: #83, top center.
MG gearboxes are not nearly as mind boggling as this picture would lead you to believe. Taken in small sub-assemblies they are very easy to understand, and moderately easy to service, with no special tools required. And that mysterious gearbox oil pump? Yup, it really works, and you really can tow an MG for long distances without disconnecting the driveshaft (as long as the oil level is up near the full mark.