A method for installing a heavy and bulky switching module, in particular a static transfer switch, in an electrical cabinet, by way of an installation kit to make the switching module easily removable and interchangeable, regardless of its size and weight. The electrical cabinet is equipped with the installation kit including at least two support rails, extendable between an extended position outside, and a retracted position inside, the electrical cabinet, and forming two parallel rolling paths. The switching module is equipped with rollers in two parallel rows, arranged to circulate on the rolling paths to enable movement of the switching module relative to the electrical cabinet by pushing and pulling with minimal effort. A raised transport pallet is also used to facilitate handling of the switching module outside of the electrical cabinet by a simple industrial truck, without resorting to a lifting device.