If you can't find a good used one from another pickup truck for less $ on craigslist or ebay... I believe they're the same part as on '55/'57 Tbirds.
Part number 6754 at most any Tbird resto parts house... approx $24 + tax & shipping
https://www.classictbird.com/
https://hillsresto.com/
The machined hole in the block has a slight taper to it and may have a tiny lip at the top to get past. The tube fits into the block about an inch.
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