OK, the fluid sensor. If you're happy to not have some indicator light to tell you the level, you can bypass it. It'll either ground the wire when the fluid's low or the opposite. First, take the wire off the back, if the low coolant light is on, attach the wire to the negative of the battery or any metal part nearby, the light should go out. Problemo solved!
The speed sensor is a bit tricky. it's either the sender (a little device screwed into, normally, the gearbox) the wiring (unlikely) or the computer (which would be expensive). The wiring, if that was the prob, should be easy to spot, as it would normally happen near the device or if the wiring loom is physically damaged, like rubbing against something. It is extremely rare for a fault to occur within a wrapped wiring loom (but it is possible). My guess would be the sender, as it is in the most extreme environment (a hot vibrating slab of metal). Replace it first. Process of elimination.
The wiper thing DOES sound like wiring fault, mainly because with stalk controls the wires get bent back and forth a lot over the years. If it's wiring, it will be right at the steering column or the switch.
Dome light switches are another common fault. Again, they are a crappy switch that earths the circuit. They will have a single wire on the back of the switch. If the light comes on just play with the switches in turn with the door open (repeated pushes of the switch) which may help to track down which button is faulty.
Buy a can of black spray paint for the hood.
The windshield you'll have to call in the pros.
