In a small bowl, mix together the cream cheese, mayonnaise, dill, garlic powder, salt, pepper, and lemon juice until smooth and well combined.
Lay out the bread slices and spread a generous layer of the dill cream cheese mixture on each one.
Arrange the cucumber slices in a single layer over half of the bread slices.
Top with the remaining bread, cream cheese side down, to form sandwiches.
Gently press each sandwich and slice into halves or quarters for dainty finger sandwiches.
Serve immediately, or cover with a slightly damp paper towel and chill until ready to enjoy.