Yeah with an OS#08 you know its the right temp plug. Sorry you just went and got it, but..be patient.. Order more than 1 for later

The pressure line should not affect the idle as much as the plug and your low speed mixture. But the Pressure lne should only be as long as you need to get to the tank.

When you took out the valve did you reset all needles to factory settings??


EDIT ADDED: Good Find On That Pressure Line Article Never Saw That But Is In Line With My Thinking