MG, For overhaul of the manual transaxle, cleanliness is always pricey especially because dirt spread over the internal parts when the exterior is dirty. All parts must be washed with solvent and then with compressed air, it is forbidden to use cloths and rags. Lube seals should not be lubricated with transaxle oil and thrust washers should not be lubricated with medicaed petroleum jelly. Aluminum bolt threads should always be greased with clean transaxle oil during installation and one may use anti-seize to avoid galling. When disassembled, you will have to take out the detent ball retaining bolt and the housing bolts then, you will use a hammer to take apart the housing. Remove the reverse idler gear shaft and shift forks for checking the wear on it. Check distances between different gears and spacers and in the event of deviation from the standard, they should be taken out. If some measurements are OOT, then replace the concerned parts. During its assembly, all the components must be free from contaminants; bearings and seals must be mounted; bolts must be tightened to specific torque. Check all components for wear and fit on the final assembly and before installing and finalising the position of the shift arm and detent mechanisms. Last, verify the clearance, and set all positions to meet and torqued to the standards, replacing the snap rings.