Full Size GPU in slim case with watercooling

[lamourlamorgue]

So, I'm thinking about building a small form factor pc, probably to use as a HTPC.
Space is an issue, but I would also like to be able to use it to game on.
So a high end GPU is a must

This isn't asked about hardware specifics but more about using 90 degree PCIx16 risers/flex cables coupled with water cooling to fit it into a smaller case.
I know that fitting the radiator into the case might be an issu
e
Are their other issues that have to be dealt with, and how would you tackle them?

for the sake of it, let's assume unlimited budget.

 

[capt_taco]

The most obvious question is: Why NOT use a bigger case? I mean, you can try to force your way through problems like this, but it's much easier if you just use the right parts for the job.

 

[lamourlamorgue]

Space is limited.
also it's fun to be challenged to design something.