I happened to watch recently a video which may be helpful.
If you search youtube for "Porsche IMS fix 6" and go to 6:10 in the tape, he describes a DIY tool to lock your cams. The link is:
https://www.youtube.com/watch?v=nRmB53bALf8, but in case it doesn't work, do the search.
Having replaced a solenoid, in the car, I'd highly recommend doing your fix with the engine out of the car. You'll be much happier.
I'll try to include a frame grab of the tool to save you some time.
Hope this works for you.