The problem I have is that when I place mezzanine board on top of hikey or dragonboard 410c and I also plug secure96 on top of the mezannine board, some of the grove sensors below the secure96 board cannot be used. Therefore, I would like to ask which type of pin extender do you suggest to purchase and use in order to simultaneously use secure96 board and all mezzanine grove sensors on the Hikey or dragonboard410c board. I tried some extenders with Arduino and Raspberry, but they don’t seem to fit. Thanks.
To get more height I normally just use a 40pin socket (the pins on the bottom generally plug into the socket below).
Take a close look at the schematics for both boards though just in case you need to desolder any components (I don’t think you do… although it would certainly be wise to not connect anything to the microUSB on the secure96).