The easiest way for you to learn this would be by purchasing a Haynes Manual for your cars make, model and year. The run about $20.00 from your local auto parts store, and will include step by step instruction, need tools and pictures. It will also have a lot of information for other repairs as well should you choose to do them yourself.
RepairPal Certified shops can diagnose and repair your 1993 Cadillac Seville. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.