86' Coupe GT O2 sensor

[s4qtro at bellsouth.net]

    Dad and i were searching for an exhaust leak near the Manifold and i noticed a couple of wires that werent plugged in.  apparently they were for an O2 sensor that isnt plugged in.

    There is what looks like an original cover on one of the wires and a plug screwed into the exhaust manifold that too looks original or it has just been there for a LONG time.

    My question is this:

    Could my car be a euro spec brought to the us?  or did someone just not feel like spending the extra bucks to put an O2 sensor in and screw a bolt in?

Thanks,
Head