The "gen1" T-stat housing is Weak and once the flange is damage won't seal or leak soon after.
Pull off and look a flatness of the flange. Use anything flat, light one side and look thru light at other side.
ReRead your first http://www.fiero.nl/forum/Forum2/HTML/144700.html
and search PN for "gen2" w/ better flange in http://www.fiero.nl/forum/Forum2/HTML/144348.html
If you keep damage "gen1" part.
Carefully Flatten the Flange.
Then use longer bolts and make spreaders to load the housing better then old holes.
Some flat iron w/ 1 hole spanning the whole piece maybe including bent edges might make it work.
Use a New gasket and use High Tack or Super 300 and paint both sides.
Sealers won't work w/ any wet gasket. Most times No even if dried out.
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