No, I wouldn’t worry about that. The plugs look like crap because the engine is farting/running lean. Once the air return line if fixed, put the engine on a boat so you can get the needles properly adjusted. Run the engine in gear at WOT so you can dial in the high speed, then slow it down so you can dial in the low speed. Make sure you have mixed the fuel at 16:1 for you initial run, just in case the engine is a little tight/rusted from sitting.