Go to your local news stand and purchase the latest edition of "Hemmings Motor News", if what your looking for is not in there, it doesn't exist.
The official website, Mercruiser Parts will easily enable one to find spare parts for their Mercury Mercruiser. Alternatively, there can be any number of people selling spare parts on eBay.
A boat shop
Parts for older vehicles such as a 1950 Ford would be difficult to find in regular automotive stores. It's best to find a mechanic or shop that specialize in restoring vehicles and seek parts from them.
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You would find water ice inside some of the shaded parts of craters.
The Mercury Mariner is a vehicle. If you are looking for the vehicle, a local Mercury dealership is likely the best place to look. If you are looking for parts, a local auto shop might have them. If not, they would likely be able to tell you where you can find parts locally.
You can find the air conditioner schematic for the 2000 Mercury Cougar online at places like Parts Train. You can also find this schematic in the Chilton's repair manual for the vehicle.
Try gunpartscorp.com
Modern Capri Parts.Biz specilaizes in ONLY 1991-94' Mercury Capri parts. They have a giagantic online catalog with a whole section devoted just to transmission parts for the Aussie Built Mercury Capri & you can shop "24/7" to boot!! http://shop.moderncapriparts.biz/catalog/CatalogDisplay.cfm?parent=1613&cid=148
You can find a front door latch assembly diagram, for your 1996, Mercury Cougar from the manufacturer website. Many auto-parts websites will have the diagram.
== == Go to a local FORD dealer , ask for one from the parts counter.
Why abuse a nice old car? Parts will break and they are hard to find not to mention expensive.