Drop-in resolution
Miyota 9019 vs Seiko NH72 (TMI NH72A): do they swap?
Whether the Miyota 9019 and Seiko NH72 (TMI NH72A) share a case, and what changes if you move between them.
Different footprints. The Miyota 9019 is 26.00 mm x 3.90 mm and the Seiko NH72 (TMI NH72A) is 27.40 mm x 5.32 mm, so they do not share a case. This is a choice between platforms, not a swap.
The Miyota 9019 is a slim no-date 90-series automatic, in clean-dial dress and field watches. The Seiko NH72 (TMI NH72A) is the hacking, hand-winding skeleton member of the NH3x family.
They differ in diameter (26.00 mm vs 27.40 mm), height (3.90 mm vs 5.32 mm), beat rate (28,800 A/h (4 Hz) vs 21,600 A/h (3 Hz)), calendar layout (centre seconds, no date, slim vs full skeleton, no date, hacking), winding behaviour. A 90-series slim automatic at 26.00 mm x 3.90 mm without date, sharing the 9015/9039 footprint and dial feet. It drops into a 90-series case built for a clean no-date dial.
Matching diameter and height is necessary but not sufficient. A donor is only a true drop-in when the dial-foot positions, hand-hole sizes, stem length and calendar layout also match. Two movements can share a case and still need a new dial, re-broached hands or a cut-to-length stem.