After modification, use a multimeter:
Remove the clip, reassemble the laptop, and power on.
A Sandisk Cruzer Fit with no detection was opened. The 8-pin Winbond 25Q80EW SPI flash (3.3V) was read with a stock CH341A – verification failed at 0x0000. After performing the 3.3V mod (cutting pin 28 and jumping to LDO out), the chip read perfectly. A clean firmware image was flashed, and the drive became fully functional again.