several of those adapter blades look like they don't need more than the width of the slot (not whole bracket).
a couple of those cheap ones (1,3,4) did ok in tests. that red bracket might be close towards the key (by the i/o bracket) but i'm sure if you loosened the screws to that gpu, you might gain 1mm gently pushing a little then tightening back down. but it does look to have the wiggle room to push a blade in that slot.
pretty sure the waterblock and plastic/cheap blue tape on the extensions can live so close/touching to each other.
Remember the golden rule of statistics: A personal sample size of one is a sufficient basis upon which to draw universal conclusions.
Upload the computer to Dropbox and provide a link to it so others may download it to examine and give advice for repairs.
Asus P8Z77-V Pro
PNY 1311 240Gb
EVGA SuperNova 750 G2
Stryker M [hammered and drilled]
Ducky Zero [blues]
Klipsch ProMedia 2.1
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