I feel for you. I hate following idiots that 'think' they know what they are doing. I think there are two options. Option one is get a complete wiring harness from Painless Wiring and replace it all. Expensive and incomplete as you often need to re-use your own connectors. Option two is use a factory service manual wiring diagram and start tracking down stuff and making repairs. Cheapest but most labor intensive. I would do that as I prefer to solder all my connections, shrink wrap and seal, which prevent problems down the line. I also like to know what and where everything goes and make improvements. These cars are actually pretty simple to wire up. The entire wiring harness for the entire car will fit in a 5 gallon bucket. I know it is scary looking at all that wiring, especially if it has been %$#@$% with. But you can learn a lot and straighten it all out. Patience is a must.