If you want something new, there are numerous choices.
I like looking for cheaper options like stuff in the junkyards. ALL the Mopar minivans and PT Cruisers that I've seen use an inline cooler like this:
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They mount right here:
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They are really simple and only need to be mounted where they can get some air around them. It does help to have them in the path of air but even if they are under the battery tray, they will still shed some of the heat. Sometimes a difference of 15 degrees can be enough.
You can buy new ones like this one from Dorman....
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I'm told it is under $50. The junkyard ones were ten bucks each. I grabbed a few and keep them for future projects.
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