Countless ideas.. I feel that. I don't know a huge amount about product design, but it seems to me that any company that could (and would be willing to) design and produce one-off plastic products could in theory make whatever design you would please. As many design firms are using 3d printing nowadays, I could see this being a possible way to do it.
Seems doable to me though; I don't see a reason to why the rear of the stock housings couldn't be modified (replaced) to hold whatever lights or light assemblies you'd want. Then just fit the stock fronts back onto them. Might want to look into contacting a company or two. They may see it as an odd request but, I'm sure for the right amount of $$$ they would be willing to take a crack at it. Just depends on how much thought and effort you'd want to put into it!
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