How big is a early a body trunk?

Hi From Australia,
I think my 1964 Dart GT has 18 cubic feet of boot space, I'm sure I read that in the Owner Handbook, and my 1964 Valiant AP5 was about 15 cubic feet.
As an aside, we had a car called a Leyland P76 which had a boot (sorry, 'trunk') so big you could fit a 44-gallon drum in it. 44 real gallons, not those USA 'diet gallons'... HaHaHa!
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