To find a compatible harness, you need to:
1. Identify your engine: Check the engine block itself for the engine code (often stamped somewhere). Your vehicle's documentation might also list the engine.
2. Use the engine code to search for a harness: Once you know the engine code, you can use online auto parts stores (like RockAuto, AutoZone, etc.) or salvage yards to search for a wiring harness specifically for that engine and year. Using the engine code is crucial for a precise match.
Simply stating "1987 Dodge 150" isn't enough information to find the correct wiring harness. The engine is the key factor.