If I understood my A/C service man correctly ports can be added if the system needs to be opened up for repairs.
External ports were added on my A/Cs. Make sure to paint one red and one blue.
Yes to both Dean and Chappell. Ports on a SCS unit is a pretty good indicator that it has been worked on. Adding ports is the only way to break into the system to replace a compressor. The red and blue is to indicate high and low side for hooking up to the gauges. Since you can't see into the unit like a typical setup, it's a great practice to ID the ports. Red is high, blue is low.