lol gl the closest I think you will get is in the manual. I do believe they have a picture of the noid but not a diagram of it. And you spent hours searching? well chances are bud there is not one.
I can point you in the direction if you want to ever buy one. I can find you a link in a hot second but sorry I can not assist you.
Edit: I found this on Matrixowners.com Idk if this is what you are looking for but Macky takes apart the solenoid and he shows you some pics.
Maybe I did help after all