First, label the two ribbon connectors with top and bottom and be sure which side attaches to the main board and which side attaches to the secondary board on the right. This is important because these connectors only go on one way and can not be switched.

Next, remove each connector like you did earlier with your nail or a small flat screwdriver.

Using that same small flat screwdriver, you will need to remove these two connectors from underneath the main pcb. Pry gently from each end of the connectors until they come loose.

Using some tweezers or a very small set of needle nose pliers, gently remove these two connectors from the top left of the main pcb. Be careful not to pull on the wires, ONLY the white connector ends to pull them out.