Yeah drop the card down to the lower PCI-E lane and run at 8x bandwidth.
This would then give me a bit more space to rotate my HUGE NB cooler round to sqeeze under my CPU HSF. This would "hopefully" free up enough space to wedge a HR-05 Plus GPU cooler in. God this case is busy
Moving it down would be a good temperary solution. You probably wouldn't even see any performance loss considering that your CPU is holding that GPU back already.