It is a difficult job for the DIYer to overhaul a manual transmission. The process involves the disassembly and reassembly of many small parts. In addition, measuring the clearances, if applicable, may require using a select-fit spacer or snap-ring. If the transmission is removed and installed by a competent individual, any problems that occur as a result of the transmission work will not be the responsibility of the company, either directly or indirectly. Overhauls should be left to a competent repair shop, as the time and cost involved is often more than that of a rebuilt unit. In fact, rebuilt units are available through some dealer parts departments, as well as many auto parts stores. An inexperienced mechanic can rebuild a transmission if they take their time and use the correct special tools to not miss anything. The internal and external snap-ring pliers, bearing puller, slide hammer, set of pin punches, dial indicator and maybe a hydraulic press or such are all essential tools for the job. All of this must be done on a stable workbench which is large enough and the vise or transmission stand must be used. While taking apart something, notes should be made regarding the positioning and securing method of every component. Familiarity with the defective section of transmission can simplify component inspection and substitution, as a number of faults do relate to a part of the transmission.