Modular vehicle and corresponding method

The vehicle has slider shoes fixed to a structural chassis frame (3) and a cab interior and rear storage space separating structure (33) with a carcass (35). The structure and backrests (11a) of seats are connected together to define an assembly sliding along the shoes and relative to a base (11b) of the related seats to reduce and increase the depth of the base in slid position towards front and back of the vehicle, respectively. An independent claim is also included for a process for rendering a vehicle modular.