Fork/headset issue

[Jermssss]

Hi, I'm wanting to put a 1 in threaded fork that has a 27.0 crown race into a 78 schwinn speedster. The headset that is recommended for 27.0 is a tange passage jis headset with 30.0 mm cups. 30mm seems too small for this frame, can I just use the cups that came with the frame?

 

[twojs.bike]

I think yes. Does it fit?