Combine all the ingredients for fruits in a non-reactive bowl. Cover and let soak overnight. If you do not have the time to wait, place uncovered in microwave and heat until very hot. Cover and let it cool down and rest for about an hour.
Grease and flour pans and set aside (SEE NOTE 2). Preheat oven to 150°C/300°F.
In a large mixing bowl, beat brown sugar and oil with an electric mixer until well combined. Add the eggs, one at a time while beating for 20-30 seconds after every addition.
Add the salt, cinnamon, all-spice, nutmeg and corn syrup and mix. Add the cocoa powder and mix well. Gradually add the flour, a cup at a time, combining each addition to the mixture well. Add the baking powder and mix again.
Slowly pour in water while mixing the batter. Then add the fruits including the liquids, if any, and the nuts. Mix well.
Spoon the batter into the prepared pans, filling each up to 3/4 full. Decorate the top with maraschino cherries, dates and nuts as desired.
Arrange the pans on a baking tray and place it on the middle shelf of the oven bake for 80 minutes to 2 hours depending on the size of the pan. (SEE NOTE 3) Or until an inserted toothpick to the center of the cake come out clean.
Remove fruitcake from the oven. While still hot, poke cake with a skewer in several places. Brush or drizzle with rum or brandy.
To age or ripen, wrap them in cheesecloths soaked in rum or brandy (mostly damp but not dripping) and place them in a plastic bag or tin box. Let it sit for up at least a month re-brushing with the same liqueur at least once a week to keep them mist. If time is too short then age it for at least a week.