In a large bowl, whisk together pumpkin puree, crushed pineapple and juice, oil, eggs, and vanilla extract.
In another large bowl, stir together flour, sugar, baking powder, salt, pumpkin pie spice, baking soda, and cinnamon.
Add the dry ingredients to the wet ingredients, and stir until just combined. Do not overmix.
Fold in 1 cup shredded coconut and 1 1/2 cups chopped pecans.
Lightly grease a 13x9-inch baking pan.
Spread batter evenly into prepared pan.
Bake at 350 degrees for about 45 minutes, or until edges are golden brown, and a toothpick inserted near the center comes out clean.
Remove from the oven, and cool cake in pan on a wire rack, but leave the oven on (to toast the garnishes).
While oven is still hot, spread remaining 1/2 cup shredded coconut and remaining 1/2 cup chopped pecans on a small baking sheet.
Bake for 1-2 minutes, stir, and bake for another 1-2 minutes, or until they're toasted, golden, and fragrant. Watch closely because they can burn rather quickly -- toasting only takes a few minutes total.
Set aside to cool completely.
Prepare cream cheese frosting.