69 with 3.75 Backspace???

Looking at the possibility of getting some new wheels. I kinda like that Cragar SS/Torque Thrust look. I see that Summit has these Eagle 211's for a decent price, about $100 cheaper than the Torque Thrusts. For the front I would get a 15 X 7 which has 4 inch backspace, no problem here. On the back I want a 15 X 8 which in the Eagle 211,s has a 3.75 inch backspace. I know ideally this size wheel should have a 4.5 inch backspace but I was wondering if the 3.75 would work. These Eagle 211's even have a 3.75 backspace on their 15 X 10's.