I applied through a staffing agency. The process took 1 day. I interviewed at RM (Didcot, England) in Apr 2012
Interview
You apply for the position through a recruitment agency which call you to run through a few basic things such as right to work etc. From there you go for a one on one interview in which you fill out an application form with all of your available details as it is a temping agency. From there you are taken to a room in which you do a few basic numerical tests, dyslexia tests, colour blind tests etc and are asked about you availability in relation to hours.
You then are give a computer and are shown how to preform a number of steps in the assembly of the computer, you then have to repeat the afore mentioned steps in under 5 minutes. You have some cards with detailed instruction of what you have to do if you can not remember all the steps.