I have experienced recent meltdown of my fuse blocks, so am entertaining preventive maintenance of the relay board with disconnect and cleaning of all contacts, etc. Has anyone disconnected all of the relays on this board (under passenger footboard)? What about the large gauge conductor to the shunt bar? Are there any pitfalls to look out for? Any snakes not anticipated? In addition, has anyone a simple approach to cleaning (abrasive - sand paper) the inside surface of the female tab connector of ALL of the millions of connectors on the F-cars? The male tab connector is easy to clean. The female has the rolled-edge that makes all attempts to clean laborious and unsuccessful. Experience is appreciated. Thank you. Jim S.