Fast Forward to October...If anyone stumbles upon this post and wants to know what i ended up using and how the Sport Special grill turned out...
Used all this stuff...washed and scrubbed w toothbrush, then again with pipe cleaners, then scrubbed w/clay bar & Mothers, removed white over spray with acetone, but it removed some of the original black paint. During this process i discovered the Lt grill was all but broken in half...used West system's G/Flex to repair all the cracks and JB Weld to fill in the missing chunk. Masked and protected area's I didn't want to repaint. Painted Flat black. Used Cleaner Wax/make-up Q-tips(lots!)/micro fiber towels to clean/polish and brighten original paint to match repainted areas.