Hi guys, i've another quick question

We have checked all the abs sensors and they are fine (reading between 1-1.3Kohms) So we now assume its the abs ecu. How do you get inside to take a look. Dont think i'm some novice thats going to mess it up with solder blobs, i am actually an electronics engineer so before we take it to the ecu doctor i wouldnt mind a look? I have loosened all the clips but the lid wont come off any ideas?
cheers
Ant