2000 jaguar xk8 how many gallons of gas does the fuel tank hold?

20 gallons- with 2 in reserve (when tank gauge reads empty). Plenty....!

This is within a couple of tenths of a gallon; I don't have it in front of me at the moment. It is 17.6 gallons "on the gauge" and 19.4 counting 1.8 gallons "reserve" that doesn't show on the gauge (after the gauge hits empty).