I'm not up on fiddling with the internal affairs of a lens, so most of my work comes to fitting a whole lens assembly back onto the camera.

In this case I usally just prop the shutter open, if it lacks a B setting, and fitting a piece of velum onto the rails of the mf or 35mm cameras as a surrogate ground glass to allow the infinity focus to be set.

I usually walk out the front door in the evening , and work on focussing onto a streetlight three or four lights down the street, with the focus scale set on infinity.

The test chart you have may be useful of there is some element of the lens that you have apart, and are not sure which side should be mounted which way when putting it back together.