ADF inverter PCB 156 Chapter 6 Removal and replacement C8523-90921 Figure 143. 2 Remove four screws (callout 1) and remove the inverter retain ing plate (callout 1 2 ADF inverter PCB (1 of 2) 3 Disconnect two connectors (callout 3). 4 Remove three screws (callout 4). 5 Slide the ADF inverter PCB assembly (callout 5) up and lift to remove it. 4 3 5 Figure 144. ADF inverter PCB (2 of 2) 3 Disconnect two connectors (callout 3).