How long do spark plug wires last?
Very common to see arcing after moving them to change your plugs - this is why most shops won't just change plugs but insist on Cap rotor & WIRES. The wires were probably servicable before you changed your plugs, moving them around to change the plugs was enough to break up the conductors inside the insulation and cause arcing through said insulation.
Remember, suppression wires (what all of us run to avoid radio/electrical interference) aren't a METAL conductor (wires like under the dash) surrounded by an insulative layer of rubber, plastic, or silicone. Supression wires are a Carbon fiber conductive element inside multiple layers of insulation. CARBON FIBER is brittle (compared to malleable metals) and when flexed will crack.
BTW that burning sensation in your arm go away yet?
"don't force it.........
Get a bigger hammer."
Life IS a comprehension test!