I had a pair of evo 40 (the first version).
I had to remove the 6"5 medium drivers to access tweeters.
What i am not sure about:
External plastic was maybe maintained in place
by some sort of hexagonals head's screws, or a set square / T square.
All i remember is it was not easy to remove it and first time i tryed to dismount the plastic with a mini crowbar , it removed wood furniture cover.
About tweeters, it's possible to find cable been soldered.
And it's easy to hurt neodyme.
Oh i just edit it, he already fixed it
I keep my message as a warning, not every wharfedale speackers are like his emeraude line.