My son would like to be a train engineer but he has dyslexia and has failed the assessment 3 times more specifically the switches where one light goes either black or white and you have to say which is defective, I have tried to teach him but it is not sinking in, he is very capable and passed all the other aspects of the assessments and is very good with mechanical things, does anyone know where I can get some practice material? the test is run by SHL and I cant find anything. Many thanks in advance.