I'd be packing them in a box or boxes, that is loaded with crumpled tissue paper as cushtion, and perhaps bubble wrap underneat to prevent any sinking. And I'd make sure there was lots of room between each on. And I don't know if I'd be doing more than one layer.
Depending on how many you have, I would lay them on a tray lined with a towel to also avoid movement/sliding in the car. You may use neatly folded paper towels in between the taco shells, this may help it from collapsing during transport as well.