1956 f100 gauge differences

 Rifling through some parts,  found a box of bits in which contained two 56 instrument clusters.

Thing is this: both are obviously 56 instrument clusters, but the gauge layout is different. So, I suppose somewhere along the line someone changed the arrangement of the gauges. Anyone else struck this?

On the top cluster they are all gauges, but gauge 2 on the left says ch/dis which I am guessing is battery and yet gauge 4 is ammeter (I am assuming) as it has 0 10 30 reading on the gauge. Why have both? Gauge 1 is fuel and 4 is temp, so they are kinda normal.

However: the cluster below it has temp and fuel reversed and the middle two gauges are idiot lights. They look like factory items.

To cut a dreadfully long-winded question to size: is there a CORRECT line up of gauges? Not that it really matters.

I decided to pull the clusters apart as I wanted to change the top of the cluster bevel with a new chrome one, and discovered things were not as good as they seemed...