If the backspacing is 7.9" then you'll also need either a big spacer or an adapter as the frame notch gives you around 1.5" more in total backspacing.
GN's with frame notchs run a 325/50/15 with a 5" B.S., that's 6.5" towards the frame total so you'd need at least a 2" spacer or adapter. ( 8.6" Vette total vs 6.5" GN Frame Notch Total ).
Good info thanks GNVYUS ....thats a huge spacer though ...maybe i should go with a 10 inch or so.