What's this wire?

[TopBanana72]

Very nice so why is that on dual?

Here is the dual ballast resister and ecu. I never unplugged anything from these when I pulled the engine..

 

[T2R9]

Car could have been equipped with a heavy duty alternator.

 

[Nacho-RT74]

As mentioned on my previous replies, originally the splice should be down the tape and the only blie with yellow trace is the ECU wire...

Now, that heavy duty alt wire... is new to me. Cool.

 

[TopBanana72]

Car could have been equipped with a heavy duty alternator.

View attachment 1132211

Could be, it is not the original alternator. It dates to some time in the 80's. The fender tag or broadcast sheet doesn't mention it, but that makes sense looking at that diagram.