Learning how to fix a significant wire rats nest is going to take time, especially if your electrical skills are limited to start with. If this is the same car you are trying to flip then wanting to keep your costs down (not buying a engine wiring harness) makes sense. However, the alternative is spending a lot of time figuring it out. What is your time worth? Unless you put zero value on your time, depending on how many hours you think it might take to solve the wiring, you might be further ahead buying a pre done wiring harness.
Just to keep it even more maddening, adding $500 of new parts won’t increase the selling price of the car by $500.
Getting the car running will go a long way in being able to sell it quicker, providing the price is realistic for the condition of the car.
