1. The small metal tube going from the rear of the block to instrument panel is the oil capillary tube, so there is technically not a sender, just the oil pressure from the oil galley in the block. If you are running an electric Autometer oil pressure gauge, you will need the corresponding oil pressure sender, to match your gauge.
2. I am not sure why one would flash faster than the other, but grounding is a very common issue with the lighting systems on these truck. Check current at the sockets, to determine, for sure if it is voltage, amperage or ground.
3. The headlight switch has a rheostat in it and by rotating it counter-clockwise, the dome light will light and by rotating it clockwise, the dash lamps will dim, so you need the switch rotated counter-clockwise, just before hitting the detent, thus the rheostat is in the highest setting and the lights are at maximum brightness. Have you checked the sockets on the back of the dash cluster, to be sure there are no faulty bulbs? This will cause the backlight to seem dim.
4. Chrome-plating or powder-coating the hood springs will not cause them to loose their optimum spring-rate.
