I'll also one up that and give ya a part number (I just found the post on FTE - did NOT research myself, as of 2007 it was still available per Number Dummy (a revered god amongst the ford guys on ford-trucks.com)...
quote from ND:
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Uh...did'ja happen to stop by your local Ford dealer?
One reason these upper water outlets crack, is ppl remove them, see no thermostat there, then install one. This cracks the housing because the t/stat doesn't go there, it goes elsewhere. The thermostat fits into the water outlet that's bolted to the outside of the waterpump.
E3TZ8592K .. Water Outlet-Upper
Fits: 1983/84 Ranger 2.8 / 1984 Bronco II / 1986/87 Aerostar 2.8.
>>> Still available from FORD. Suggested list price: $11.71 <<<
If your local dealer gives you the brush-off saying...."Oh, sorry the part is obsolete" (the usual bullspit), contact FTE sponsor Direct Ford Parts (Gaudin Ford-Las Vegas NV)..they'll fix you right up, and give you the FTE discount ($10.74 net). DFP's link is on this page.
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