A modular skid mounted oil production system, comprising multiple skid sections that are connectable via alignment pins coupled to the skid beam structure. The alignment pins having a fork connector that is connected to a knife connector. When the skid sections are connected, the piping, electrical, and pneumatic tubing connectors are connectable to the other corresponding skid piping, electrical, and pneumatic tubing connectors without the need for welding or field construction of connecting components. The modular skid oil production system is capable of expansion or contraction as required by the operation of the system. For example the system includes removing a skid section having a larger separator and replacing it with a skid section having a smaller separator, without the need of welding or field construction of connecting components.