Ice build-up in freezer - Kenmore Model...

Question

My Kenmore Frost Free with bottom freezer is icing up and I need to check if the drain tube is clogged. There is not a panel at the back of the freezer inside the compartment to remove, only the complete top panel that does not appear easy to remove.

Is the tube on this model at the back on the outside of the unit or how can I locate it? Thank you so much!