I just bought a used Yamaha RBX 374 bass and I am looking for information to get a couple parts that the bass is missing. a)The bridge is a black Spector style bridge that is missing one black height adjustment screw. What would the correct part or dimensions be for this height adjustment screw? b)The truss rod adjustment is at the body/neck union. The body has a dug out area to allow the tool to be inserted. The dug out body area is to be covered with a black plastic cover with the cover joined to the body with one screw. What is the correct part number or name of this black plastic cover part? Any idea where I would be wise to go to get these missing parts? Thank You.