Preheat the oven to 300°F, and grease a Bundt or tube pan or a few loaf pans really well; coat with flour and tap out the excess.
In a medium bowl, stir together the flour, baking powder, baking soda, salt, cinnamon, allspice and nutmeg. In a large bowl, beat the butter and sugar for a few minutes, until light and creamy. Beat in the molasses and orange and lemon zest and juice.
Add the flour mixture in 3 parts, alternating with the brandy, rum or juice in 2 parts. Stir in the fruits and nuts and scrape into the pan.
Bake for 3 1/2 hours. Joy instructs: “The cake may appear done at 2 1/2 hours; simply ignore this.” If the cake is darkening too quickly on top, cover it loosely with foil for the last 30-60 minutes. Cool in the pan on a wire rack, then invert onto a plate. Store well wrapped at room temperature.