For those that are interested this is how to remove the plastic housing from the Wyse WT9450XE.
You will need something with a broad thinish blade. A screwdriver might do. I found an old PC expansion board backplate worked very well. The 'tongue' at the bottom of the one I had was fine, but another I subsequently tried was too short.
Another alternative is to something like an old credit card. I had a (now useless) Sears card from a previous visit to the US. Snipping a strip off the top using a pair of scissors gave me an ideal tool for this job.
Essentially the housing is held together by five latches where a moulding on one half (the side with the access hole in it) lodges into a hole in a tongue sticking out from the other half.
Just past the 'latch' there is a slot in the plastic. By pushing a suitable tool through the slot you can depress that tongue enough so that clears the latch moulding and the housing can come apart.
It's as simple as that!
There is one additional latch that catches in the metal work. This is at the top-rear of the case. It just has to be gently pushed to free the catch from the metalwork.
The yellow arrows show the fixings are.
The slots are on the U-shaped bit of plastic that surrounds the access hole to the circuit board. You need to peer into the central slot that runs around the center line of the housing. A torch or light of some description may help you here as it isn't the easiest thing to spot a dark slot in black plastic in the dark of the slot!
Here's an attempt to show you what you are looking for. The photo has been taken with the case apart, but hopefully you get the picture.
Any comments? email me. Last update October 2012