In a 9x13 pan, combine all the wet ingredients (oil, juice and eggs). Using a fork or a whisk, mix until combined.
Add the dry ingredients (flour, sugars, baking powder) and mix until a batter forms.
Remove about 1 cup of batter from the pan and add the cinnamon and the boiling water (yes, you will need one extra small bowl for this).
Drizzle the cinnamon batter, and, using a fork, marbleize it.
For the crumb topping: In a larger bowl, combine the crumbs ingredients until large crumbs form. Don't overmix. Best to use your hands for this step. Evenly spread the crumbs over the cake. You might have too much, reserve some in the freezer for another use (or the same cake, next week).
Bake for 1 hour, or until a toothpick inserted comes out dry.