Feather edge over spray
Because this car is being sprayed with fine metallic base coat paint it is necessary to block with 600 grit paper. Wait a couple of days to let the clear over spray from the jams set up. Block the car wet with the short blocks directly over the 400 grit scratches, a drywall sponge works really well at keeping water flowing while you block. Keep the surface wet and don't press down very hard, a light blocking is all that is needed. Wet primer blocks off quickly so only a few passes over any given area is needed, follow good blocking techniques. Block the whole car, takes about 2 hours. Scuff the recessed edges of the marker lights with fine (gray) scotch cloth but not the deeper parts of the recesses. Also scuff the lower halves of the tail light recesses, the exposed fender vent edges, wheel well edges and front grill edges. Give the over spray on the body a little extra attention, they need to contour into the primer seamlessly. You should not have blocked down far enough to expose any black. Fine metallics will flow across 600 grit scratches without showing the scratches. When completed rinse the car thoroughly with clean water, the drywall sponge works great here too. Blow out the cracks and crevices with compressed air and let the car dry completely.