ORIGINAL: Toysareforkids
It's the earlier version from the 80's, and it's 1/6 stand-off scale of the P-51A...
Just FYI if you do the math I think you will find it's actually 1/7 scale rather than 1/6. (A 1/6 scale Mustang would have a span of ~75 inches) The picture on the box top is a P-51B although I think the plans may show the Allison powered P-51A model as well.