I don't remember where I saw it. Or when.
What I do remember, is that it was a technique for adding a carbon fibre weave to the outside of existing sidecovers. But I'll explain my vision.
What they did, was vacuum bag it. And it looked damn easy actually. Layed up the carbon fibre over the side cover with resin, bagged it, vacuumed it with a shop vac and Viola! A few coats of finishing resin and some elbow grease later, he had a completely blinging carbon fiber overlay for his side cover.
Now I say, instead of using the side cover you DON'T have. Make and finish a foam plug, and just form around it. Rather than making a concave mold. Saves a big step making the mold. The bag naturally leaves some bag marks in the resin that will need to be sanded out and finish-resin top coated, but I think it's still easier than the full mold process. This is coming from someone who has done very little traditional fiberglass work!
I wish I could find the website :-(