Are you talking about the red wire that's on the same lug as the battery cable? If so, that's the wire that powers the entire car unless there's an added jumper wire at the battery (starter is used as a junction block), and it would make total sense as to why the draw stopped when disconnected, you killed power to everything electrical. Another thing I didn't see you mention checking is the horn relay on the radiator core support, it's also used as a junction block. Not everything electric on the car is fused, some are connected directly from the battery with in-line fusible links, horn relay is one of them.

 

hm, ill go out today and start trying some of those things and post back, thanks all