First of all: Thank you that you're developing a cooler which fits the Sapphire and ASRock variants. Unfortunately, I own the PowerColor variant (I think that's the last one that's not yet mentioned in this thread). Is there any information known about the PowerColor version? Is it compatible with the cooler you have in development?
If it would be helpful, I can provide some pictures of my card if you have some clear instructions on what you need to know. In addition, I'm happy to ship my card to you so you can analyze it yourself. I live in the Netherlands, so shipping to Germany is quick and not that expensive.