I can't find what this connects to. Thought with the engine in, something in the area would present itself. So this is down under the intake, close to the black metal intake brace. Brake master in the foreground.
Looks to me like it's the rear ABS sensor connector. The sensor would be on top of the trans, just behind the bell housing, if you had one. Mine is tied to the reverse light switch wire that goes down to the side of the trans.