Today I tried GR9768 (I had already did it a few months back though not timed). Despite my best efforts I could manage to solve only 59 questions in the stipulated time.
I think one problem with me (and with some of us other test-takers) is that we tend to overspend time with the easy questions in the beginning and by the time we reach the 3rd hour of the test we are exhausted and have very little energy left for doing the more time consuming questions.
How about doing the test in the reverse order i.e. Try with Qs 50-66 first, then attempt Qs 25-50 and end the test with Qs 1-25?