If the GTA rims have the same dimensions as the IROC rims, then you'll probably need 4 front rims to get them to fit. I tried putting the IROC rims on my Monte, and I found that there is a 13/16" difference in the offset between the front and rear IROC rims (that's why they're marked front and rear). At first, I had spacers and long wheel studs made up so that I could put the front rims on the front of the car, and the rear rims on the rear of the car. Eventually, I found another set of IROC rims, then I kept the 4 front rims, and sold the 4 rear rims, took the spacers and long studs off the rear, and now I just run the 4 front rims on the car. If the GTA rims are the same as the IROC rims (and I suspect they are, though I'm not 100% sure), then you'll either need to use spacers & long wheel studs as I did on the rear, or obtain 4 front rims to allow them to fit on the car. There may be some people out there that disagree with me, but this is what I know from my own first-hand experience.