4. Do I have proof that the requirements I have outlined for a specific job are really "job" related?

Again look for biased wording in the job description and training materials, etc. that could be used to support a claim of discrimination against you. Keep written company materials gender/race/age neutral. To prove that the skills that you are looking for are really job specific you will need to conduct a job analysis periodically to update what the job entails, what the minimum skills for the job are, and to determine the physical requirements for the adequate performance of the job.