Thanks for the pictures and detail steps. That helped a lot.
The following is my SHORT CUT:
I got as far as removing the plastic electrical part and removing the washer.
I was having difficulty removing the rest of the philips screws, when I realised that the protuding magnetic shaft rotates a valve and that the root of the problem was that it was sticking. I could feel resistance to turning it.
So I squirted around it liberally with choke cleaner several times until I could feel it rotate easily and return under its own spring power.
Since the main problem was now fixed I decided to reassemble from that point and save myself the harder work.
6 months have passed without any futher problem. I guess my short cut worked without having to remove the vave body.
