Servos HELP!

My way will be the following.I am going to buy an used wind screen wiper motor with an high torque (much cheaper than the geared motors from nanotec and probably as good) and the Australian Oatley Jumbo Servo electronic kithttp://www.oatleyelectronics.com/kits/k165b.html.Here is also an other option doing the circuit yourselfhttp://www.cpg1.freeserve.co.uk/servos/servos.htmI have everything else, from Iocard to drive the servo. My last concern regards the "torsion spring". It has to be custom made for the column. Any advice on that subject are welcome.GreetingsRoger