I can't beat you guys with my '48 but we did drive 1250 miles from Seattle to Laramie, WY in 1966 with our absolutely stock '51 Chev car loaded to the gills with car rack and pulling a U-Haul trailer through Yellowstone. We had a contest to see which family member could guess our miles per gallon.....of oil.....which I bought in bulk.
This and more are in the web site in my signature.
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Overnight at Lewis and Clark State Park, Montana. .
Hello Laramie. .