78 Aspen 904 tranny into 69 dart spedo cable issue

78 318/904 Aspen swap into my 69 Dart /6 car. The 69 /6 spedo cable end at tranny doesn't match the 78 904 tranny connection. What do I need to do? Is there an adapter available? Would a V8 spedo cable have the correct end? Or do I have to have a custom cable made? :banghead: