A possible problem I can see with that set up is that the struts are sitting in the channel where the water runs down. I reckon it wouldn't do them a lot of good in the long term and if the bracket rusts it might break off. Most hatches with that system have them on the inside of the hatch seal don't they? I had a local guy who came round and took off the GTV and Volvo struts and came back the next day with them rebuilt, including increasing the pressure on the GTV one to cope with the extra weight of the speakers and spoiler. When I push the button on the GTV the hatch goes up by itself. He also put it in the opposite way round from the factory because he said that it needed the seal end to be facing down when closed or it would dry out and leak. It makes sense if you think about it and works just the same. It cost me about $150 for the three of them including a 12 month warranty.
I have had that photo lurking around in my computer for years and have never noticed the struts - a fantastic idea.
Brings back memories - when I had a 78 2.0 I toyed with the idea of changing to a side mounted strut and fabbing a fold down rear seat (was going to get one from a 33) so I could fit my bike in the back.
Unfortunately, some goose did an illegal right turn in front of me and turned it into a short wheelbase version, so I used the insurance payout to buy a 33 instead, which swallowed bike easily.