Blown350ZZ4

So, here is the story. 86 Z28 is undergoing a restoration, lowering springs, shocks, A Arms and a brand new Moser 12 bolt have been installed (Stock dimensions). Anyways, car needs a fuel system and some other misc parts before engine can be dropped in and mounted up. With all of the non stock parts, I want to be 100% sure I order the right wheels which could take up to 2 months. My question is, will the lack of the weight on the car/suspension affect a backspacing and general wheel measurement?

Once I order the wheels, they are mine..... custom, you know....

Thanks in advance

Nick