How do you change oil pump 94 S10?

Your local auto parts store has aftermarket service manuals (Haynes is one publisher) for your specific make, model, and year of vehicle. It costs less than half an hour of a mechanic's time, and is invaluable for finding, testing, adjusting, and repairing things on your car, as well as critical specifications and information. It will also give you an idea of the complexity of the repair, as well as the skills and tools required for the job.