wait before you lean the bottom end us how it idles with the glow plug warmer left on. im also thinking it could be that the idle is set to low. leaning off any engine during break in should be avoided only should it be done if it is set toooooo rich. as idealy you want a rich setting to properly lube your brand spanking new engine

and the P6 turbo plug is a good plug to break it in with.