Temperature Gauge Sender Location?

My temperature gauge is not hooked up, and I can't find the sender to fix it. The manual shows it just behind the sixth sparkplug on the cylinder head, but I have nothing there, not even a plugged hole.

I have a '66 240ci I6. And my vin is after 751,001, so supposing I have the original engine (big suppose), I should have the larger style sender. Like so... http://macsautoparts.com/econoline-water-temperature-sending-unit-from-serial-751-001-c6dz-10884-b/camid/ECO/cp/JS0R3CHL1101836P/

Passenger side of the head near cyl 6.

Found it... viewed from below. Thanks.

How about on a 200, for sure not the original engine. Also, would it be the same for electronic or mechanical gauge? The sending unit is different, but the plug in place.