Rotation & angle of universal joint?

[Roland Melkert]

Orange parts are the chassis, grey parts are properly placed (I am supposed to be after step "90 deg to align with the axle again."), but blue and white parts are not properly connected.

Assuming the red axle is correctly snapped to the all grey universal joint:

Select red axle
Set rel grid
(single) Select the grey uni end (the one with the blue center)
ctrl+home (reset only ori to grid)
rotate it 90 deg as the axle is X oriented and the uni halves are Z oriented.
add the blue, white end and white axle to the selection
apply script
re snap the white axle to the white end.