1000g AU, at 31.1g/troy oz would be 32 troy ounces of gold.
and if 4 ounces of HCl and 1 ounce of HNO3 will dissolve one troy ounce of gold,
or 5 ounces of aqua regia /troy Oz of gold
then 5 ounce aqua regia X 32 troy ounce gold = 160 ounces of aqua regia,
or 32 ounces of HNO3 and 128 ounces of hydrochloric acid to dissolve 32 ounces of gold. i used the formula 1HNO3:4HCl (better to have excess of HCl than HNO3) and I would start out with less acid, and heat to get saturated solution then add more as needed.
32 fl oz= approx 0.95 liter
128 fl oz = approx 3.8 liter
my best guess