Yes the aluminium will start on fire if you accidentally get armorall on it.
LOL, stop worrying so much, I use that sprayon tire shine stuff, the stuff that you spray on in a thick foam and just leave alone. I spray it all over the face of the sub then take a soft rag and wipe it off, looks nice, attracts dust like a magnet though.
Now thats different. if there is no protective clearcoat over the sigs the spray might smear the ink. Avoid touching them all together if there is no clearcoat over the sigs.