Another Thermostat / Housing question.

Does the thermostat housing fit inside the water neck lip in picture #2?
Mine looks the same as yours. I put a small dab of cooper rtv inside the ring and "glue" it to the thermostat. Not a bunch just enough to seal it to the thermostat housing.
Does the thermostat "towers" that goes toward the radiator hit inside the housing? My aftermarket aluminum housing would hit on these towers. I notched the neck a little bit with a dremel too in order for the thermostat to fit the water neck. If not it would wobble around because it was not seating fully in the waterneck.

Comparing the two water necks I believe the new one your looking at will leave you in the same boat as the first. I think those are the same water neck.