I am in need of the schematic for the power distribution block for a 2003 Expedition. The relay labeled as R203, and called the PCM Relay, has now been replaced 3 times. Pin 5 of the relay is melting the plastic of the relay. It has been taking SIX to EIGHT MONTHS months to show any symptoms. I know because I have been checking it monthly. I now have an additional issue. I went to install a new relay and the new relay would not work. I started to do some troubleshooting and the receptacle would not hold a spade connector. I suspect that due to the heat involved, the receptacle of that pin of the relay is now being allowed to pull back from its correct position and no longer makes contact with the new replacement relay contact. How difficult is it to pull the block out to make the repair? Even if I cannot repair/replace the block immediately, I need to find the source of the current draw. What useful advice can you give on this issue?