I'm a little late to the AM/3D Print party myself, but am coming up to speed quickly. We have several at the place I work, and the program I support is employing additive and 3d printing on a huge scale, plastic, stainless steel, ULTEM. I have a couple parts, in support of an experiment, being manufactured for me as we speak.
It's hard to believe 3d printing them one at a time, vs vacu-forming over mandrel and trimming in production quantities, would make any business sense. Buuuuuuut... the retail cost of Bushwacker flares for an Econoline van, sure does make one wonder.
If your programming time is after hours (therefore free), and you have access to a large format machine (again, maybe your employer and after hours), maybe some low-cost material, heck, there's no reason why not.
The old brittle stereo lithography (SLA) resin parts, used in design concept meetings, with there limitations are really a thing of the past. Material sets have advanced light years ahead of where they were 10yrs ago. Several OEM automotive manufacturers are right now, incorporating 3d printed parts into their production product lines. Something I never imagined back in the SLA days.
It would be a fantastic process for most of us to watch via a 'build thread'.
I say "Do It!"