On a 1983 GMC Sierra, the ignition coil is typically located
on the passenger side of the engine compartment, usually mounted on or near the distributor. However, the exact location can vary slightly depending on the engine size (e.g., 4.1L, 5.0L, 6.2L). It's usually a relatively small, black cylindrical component with high-voltage wires connected to it.
To be absolutely certain, you should consult a repair manual specific to your truck's year, model, and engine size. A visual inspection of the engine bay, searching for a component matching that description near the distributor, is also recommended.
