I found this link -
Kudos Motorsports
indicating that the R32 rear sensors are identical to SR20DET (Red Top) Oxygen Sensor,
NTK, Nissan Skyline R32 GTR & SR20DET [OTD2F-P1P]
- Info below taken from link above:
NTK is the OEM (original equipment manufacture) for most Nissan lambada (oxygen) sensors.
This particular item is a direct replacement for the following applications:
Nissan 180SX, S13 (SR20DET, Red Top)
Nissan Silvia, S13 (SR20DET)
Nissan Skyline, R32 GTR (RB26DETT, Front Sensor With Reuse of Current Square Plug)
Nissan Skyline, R32 GTR (RB26DETT, Rear Sensor)