The Central American Power System (CAPS) comprises of the electrical power networks of Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. The topology of the network, the geographical distribution of the load and generation blocks, and the localized weaknesses in some sections of the transmission grid have made this system prone to frequent partial or total blackouts. At the same time, this area has the advantage of having a control center that can promote international measures in order to safeguard the integrity of the transmission network. This paper presents a gradual optimal PMU placement approach that guarantees minimum regional observability at the initial stage and full observability for the complete implementation. The paper also states how WAMS can provide real-time information to the control center for a more secure operation of the system. The practical constraints of ensuring real-time monitoring of critical buses of the network are taken into account during PMU Placement.