Can someone help me get a Tower 46 running?

On Tower's site they say something about a 2mm gap on the low needle setting. I am new to this so I have no idea what they are measuring. I know where the low needle is, but where is this 2mm measured? I have tried various high needle setting and low needle setting and I can only get it to run for a few seconds and then quit.

The low end needle was set 11 turns out from all the way in. Is this even close?

Thanks