I think taking a plain Jane car and making into a "clone" of a car you really want but can't afford or really want/already have but are afraid to drive on the street is fine, as long as it's sold that way and not represented as the real thing.
As to making a '71 R/T convert or the like, well that's different. You're not cloning, because the car was never built in the first place. It's your car, so fine, do what you want, but it's really not cloning, it's something else (tribute sounds good to me).
I have no problem adding options to my '73 Chally, but only if they are factory or factory-like. Like the Grant 860 Tuff Wheel, Harms pistol grip, '70-style hood blackout, front spoilers, etc. And I'll be adding the T/A ducktail spoiler, '70 longitudinal stripe (minus R/T letters) and a few other things. I just want to avoid aftermarket.
And, hey oldvamoparfan, nice car!