Nope, don't use any maths type software programmy stuff. TbH, for my sins, I've tried to avoid proper maths engineeringy stuff since I left university. Once Fourier Transformed, twice shy...
(now a nice Laplace or partial fraction on the other hand!)
Well finally got the disc off, the drill its i bought were rubbish! had a couple of little ones a mate gave me a while back and they cut throught the screw like butter!
Now i just need to fabricate some fixings for the hose to get rid of the ugly cable tie job!
oh, and i have the rear of the car to do, im praying they didnt bother with the retaining screws on the back....