Hmm.... probably best to retrace everything you've done so far. Could you split the difference of the adjustment made to the height of the plate?

Do the spark plugs have buildup on one side of the insulator? Rough cold idle, blue smoke and if it's there buildup on one side of the insulator can be valve seals. They're relatively easy to replace, based upon what you've done so far you can reply them.

__________________
"Rudeness is a weak man's imitation of strength" - Eric Hoffer