I had no problems w/the 1/2" spacer on the 86 gn, but I had the old motor mts. It was actually ~5/8" w/the addition of the rjc plate and gaskets. I purchased a 1" spacer for my champion int. on the 87, but I 'm considering going to the 1 1/2" spacer and a Hartline hood. I have H&R motor mts. on that vehicle.