Thanks for the input.
The twitter speaker repalcement is simple procedure IMHO.
There should be no need to remove/dissassemble the midrange head.
https://youtu.be/DP_-KRfExkE
Thats why i am not so much concerned about replacing it onsite (if possible).
Here it is some info for the midrange replacement -
https://youtu.be/7HOG1tYjPrc
with the right tools will be simple as that.