The procedures to replace an Executor in a Last Will and Testament are dependent on state and local rules, and on the procedures that govern the particular probate court in your area.
Most likely, a new executor would need to be nominated and a motion or application filed with the probate court to appoint such person. The motion or application would then be heard by the court, and beneficiaries and others with interest in the estate would, most likely be permitted to consent or object to the nomination (depending on the jurisdiction’s rules).
If this process is too complicated to handle pro se, Standard Legal suggest you find a local attorney to help; you can find an attorney for FREE here.
To easily create a new Will, see Standard Legal’s Last Will and Testament legal forms software page.