Firsty, thank you for pointing me toward hwinfo64, it works perfectly!
Otherwise, I’ve had a go at putting some fans on the heatsink.
I’ve used two 60x13mm fans (delta AFB0612HHC’s) blowing longitudinally along the graphics card and out through the back of the case (see pictures). I would desirably have had the fans mounted such that they blow directly off the heatsink (i.e. blowing perpendicular to the length of the card), but in my case I have about a 30mm gap between the Tesla’s heatsink and the graphics card next to it, so that isn’t really an option.
The mounting isn’t particularly professional for the time being, I’ve mounted one of the fans directly onto the metal base-plate that the card came with (the one that is down the end of the card near the power sockets) and the other on the outside of the case - to make a push-pull setup along the card.
In regard to performance; it is idling at 50C and under load seems to stabilise at around 70C. This isn’t a particularly thorough test, but it’s been running at load for the last hour and has only hit 70 once (seems to hold 68-69C). When I’ve made some simulations that can be run for many hours I will let you know how it handles it.