Sorry for misplaced comments about front/rear views.
Cedar strip is used for building plugs in boatbuilding, but it is a fairly expensive way to go. If you're making a plug then you are only interested in the shape and surface finish - everything else is overkill. I am making some plugs for motorcycle bodywork and have used quite a few materials.
If you are good at design, I'd recommend solid "bread and butter" MDF - lovely to work with (if heavy) and reasonably cheap - it would work well on those tricky radiused corners you've got between the sides and top. There's some photos of doing this for the head fairing of my bike
here.
But look on the positive side - the high-build catalysed polyester sanding primers are probably the most lovely product to work with that exists - I swear people would pay money to try sanding it, it's so nice to do!
Andrew