IIRC there is only one wheel speed sensor that is used for the speedo. Easy way is to get a scanner to check all the wheel speed signals. Again going by memory I think it is the left front wheel speed signal that is used, but is definitely a front.
The fuses i am referring to are in the BASE Module, this is kind of ditched in the rear of the engine bay on the passenger side, there is a window on top with a row of fuses. You will likely need to remove a section of covering just to see it. You also may have an addition cover held down by allen screws just to get in to the module box. You will see rows of modules, again the base module has a window you open to get to a row of "American-looking" fuses, not the ceramic ones we are used to on MBs of this vintage. Check those fuses. There will be empty fuse positions, that is normal, just check the ones that are there for blown fuses.
If you haven't check the BM fuses, do that first. A blown fuse in the BM could be causing the speedo to be inop and the ABS/ASR lights to be on, this can cause many various seemingly unrelated problems.
The cluster does pull out like the other chassis of this vintage. You have to be VERY VERY careful because if you tools slip off you LIKELY will chip off a section of the cluster lens and bezel when it slips.
Is this the mechanical odometer or digital? I know very little about testing the cluster. Is the odometer advancing when you drive the car or is the odometer dead too?
Here is a pic of a cluster I found online, at the right is a broken lens, this is what happens if you are careless removing it:
