Unfortunately the WM Statesman / Caprice / Grange cluster is a completely different beast to the VE clusters.
The cluster chassis is different (diferent shape and mounting points, the top mounts sit much further outward when compared to VE clusters)
The cluster main board is different (the fuel and temp guages are in different positions, slightly lower and further outward from memory)
The Fuel and Temp Gauges are raised by about 1cm compared to the tacho and speedo
The Gauge faces are completely different (4 pieces instead of the single piece for VE)
The fuel and temp needles are much longer
The clear plastic lense is a completely different shape as well (the curve is the opposite to VE models)
Here is a pic of a E3 HSV Grange Cluster to give you an idea.
So this means the following,
You will need to source a WM cluster
You wont be able to swap over the Berlina cluster board to the WM cluster chassis (It wont fit), so you will need to get the WM cluster programmed to work with your car
If you have a series II model with Sat Nav, then you will ideally want to get a Series II WM cluster (Otherwise the Sat Nav cluster display info will be broken, and you wont get posted speed limit information,
and depending on the software version you will need to press the TRIP button to reset the cluster when you get any Speed/Red Light cam alerts).
If you are interested, I have the WM E3 HSV Grange cluster for sale (Its brand new, so the kays and eberything else can be programmed using Tech2)
I hope this helps