"the odd, coke bottle shape, pinched fuselage of the F-106 that I researched the reason for it."
Actually, it was the F-102, also by Convair, that first featured the Coke bottle-shaped fuselage. That design change enabled the Delta Dagger to reach Mach 1 and beyond. The F-106 Delta Dart followed the same general shape but was bigger in every way, except perhaps for the tail fin's surface area. Bigger yet was the B-58 Hustler.
Remember reading about the embarassment of the first F-102 not being able to go supersonic. Heck, design a plane that looks like that, then not be able to outrun a F-86?
The area rule breakthrough was a BFD.
A nice (and merited) tip of the hat to the F-102, which I had for some reason forgotten about, and to the B-58, a remarkable aircraft for its time. Convair plainly believed in area rule and the delta wing.