RE: Removing the spoiler...
I’m not sure why you would want to make your R/T look like an SE, maybe your into the sleeper look and you’re planning to kick some 6 cylinder Mustangs.
Another consideration, I back my Challenger into the garage and without the spoiler I wouldn’t able to see the back edge of the trunk lid. Knowing where the car ends is very helpful if you ever have to use reverse. Which by the way, is more likely then my needing to change lanes at 120 MPH.