A long time friend called and asked if I can do a retirement cake for her husband. How can I refuse? But I need advice on the...How to! Her request is, this cake needs to feed about 80 attendees.

The request was a Wurlitzer Juke Box.

My plan was to stack and fill a 1/2 sheet cake ; 3 layers high...cover as a floo with black/white squares.
then bake 8" semi-circle (for the top).
Layer, fill & stack to get approximately 10" high of cake (squares/trimmed down a bit.

Is there a way to stack this cake so that I feel secure about the delivery?

Most of them recommend that any thing over 3 layers is considered a stacked construction cake. and needs dowlrods to support the weight. I would recommend you get the current yearbook and look in the blue pages. they are usually near the center sometimes near the back. But they give lots of help on stuff like this. If it isn't going to be real wide I would say that you could get by with 1 on each end in each layer and one through the middle through all layers. Good luck.