I installed mine a week or 2 ago, it was absolutely pain in the ass to install the brake and clutch pedals.
It took me about an hour to get them both fitted.... lol
At the end, I just used a heat gun to heat up the rubber on the back, to make it a bit softer, then quickly try and stretch it around the pedals. Might take a few goes but it will work.
As for the bushes, I have a bush from the accelerator pedal that I don't need for my GTT.