iMac 21.5-Inch Mid 2017
To open the Mac you cut the tape holding the screen down as Apple decided to glue the screen in...
The ROM is a WSON-8 chip 5x6mm (64Mbit Winbond 25Q64).
The ROM in on the top (easy to reach) side of the motherboard.
The SPI connector is a Hirose-12 but is not mounted by Apple.
The board number is along the top edge of the board, on the left side.
Medusa: Mount SPI connector. Use A4160 with arrow to edge of board (left). Plug in mains lead to read and write ROM.
Blank ROM chips and SPI connectors are available from us.