Post by B BI have an Elvira and the Party Monsters machine with burnt harness side connectors to the Backbox Interconnect Board (2 P7 and 2P6). The manual gives no part numbers for harness connectors (female).
There is information on repairing connectors on PinWiki here:
https://www.pinwiki.com/wiki/index.php/Williams_System_9_-_11#Repairing_the_General_Illumination_Input_Connector_.2F_Wiring
It's probably a 0.156 connector like this:
https://www.pinballlife.com/mm5/merchant.mvc?Screen=PROD&Product_Code=PBL-600-0484-00
Those are Insulation Displacement Connectors (IDC) where the wires just
push in. It's easier with the push-in tool. If you have a crimper you
can use a similar connector with separate crimp pins like this:
https://www.greatplainselectronics.com/products.asp?cat=81
- Kerry