after being cut you can see the edges if you pay alot of attention. backlighting was another issue.
i dont think the signal go from input to the gauge.
i see the cluster board as an extra set of inputs, it has a com link with the pcm. i think that is where the pcm gets the info for things like traction control, fuel level, pats, power generation(altenator control), oil pressure. the stock oil pressure sender is only a contact that goes to ground when there is pressure.
pin 19 of the big connector of the insterment cluster has the incoming fuel sender signal.says its yellow with white 20 ga
pin 91 on the pcm has the oss signal for the speedo. says grey with red 18 ga