To be fair, it's a very long thread. I was being lazy because it took me so long to read through it all the first time.
However, I went back a bit and I found this:
"Phase two: specialised aptitude
Instrument test
spatial skills tests
maths tests
hand-eye co-ord"
Anyone that has done it recently? Is it up to date? Did you find any particular part more difficult than the rest? What exactly is the instrument test?