This is on a dash i'm swapping because mines cracked by the radio.
Dash is from an 87 5.0 Tpi. Ok this solid purple wire Pins at the B-4 on the bulk connector on the drivers side firewall, My poor research seems to be the 9th injector power? not sure and chip is burned for 9th delete. But, Why is this black section pieced in? is it a fusible link? I thank you for any help..

 

I found that PURPLE is for the ignition, so i wonder why it's there?

 

Looks like just a wire repair, not a PN switch bypass.

 

The PO may have had an alarm installed. Either way, I hate butt splices.

 

I think your absolutely right on the alarm theory. It would be the remote start most likely.

 

solder and heat shrink it or use those combo solder shrink sleeve thnings, they work well.

 

Just picked up a butane soldering kit with heat shrink and wire loom.

Thanks.

 

B4 is starter solenoid from the IGN switch. Looks like an alarm system or remote start was installed then removed. Short section of 12ga added to make up the difference