Oh boy
W/o seeing the actual creation it is hard to help you.
Make sure the base is as big as possible w/o being distracting to the creation. Maybe put it on another base in the car?
Use non skid rubber mats under each base. Make double sure it sits level where ever you place it. Seats are NOT level!
Drive like a little old lady! LOL Be careful; watchful for any sudden stops etc.
If you can find a cardboard box big enough for it to fit into. Cut one side of the box, insert cake then seal (w/strong tape) that cut side. You don't want to have to stick you hands down into the box to lift the cake in or out; slide it in & out.
Hope that helps some.
I have delivered many cakes several hundred miles. I assemble on site. I crumb coat and then do everything else after that when I arrive. You can do it, just take a little more time to plan ahead and try to think of everything that could go wrong and have a plan to fix it.
Good luck!
Jibbies
Quote by @%username% on %date%
%body%