Those are some sweet looking badges!
Let's get a couple things straight here. The numbers / badges on the sides of a car has ALWAYS been there to tell people what you have under the hood. -NOT to tell people what "body style" you have.
Look at every muscle car made. Corvette's, Chevelles, Chargers, 'Cuda's, Mustangs, etc.............. They ALL came with small blocks OR big blocks in the SAME body. The only way you knew what was in it was by the badges or painted on emblems on the hood or side of the car. The 440 Challenger was the same car / body as the 340 Challenger. -Different hood and paint maybe, but the same body.
Leave it to Shelby to do something like put a lower-powered 428 into a car that advertises having a high-powered 427 and sell it to the public without telling them. I guess he could tell people that the 427 badge on the side was to tell people what "body style" they were looking at, but that would be typical Shelby snake-
oil.
-I better check my chili. Maybe I bought the small block mix on accident!
However, as Ron pointed out earlier, we are talking REPLICA'S here. If you want to put a 427 badge on a SC, then by all means do it. Afterall, that's what they came with originally and that is what you are REPLICATING.
Bottom line is, it's YOUR car, do what makes you feel comfortable.