I've never been in there, so couldn't say.
The spring on the pushrod should hold it against the cam. Fully depressed is injection time. Wherever the pushrod is on the compression stroke, you can measure clearance between the injector knob and the lifting lever. If you have a dial and mag base, you could measure the full lift, which occurs throughout the intake stroke.
I sit here now, watching it cover everything in the McDonald measles. After re-ringing it, it's no better. Having said that, I haven't put proper oil in it yet, just multigrade that was at hand.
Jarrod.