Some photos would help.
Apart from that... if the socket for the Kickstart has 42 pins instead of 40, then you should mount the Kickstart leaving the first pins (1, 42) open (those close to the notch).
42pin kickstart sockets means that someone logically removed the original socket and putted a 42pin one to support 1MB ROMS (although iirc, this requires a wire to Gary as well).
There is no specific kickstart 3.1 for Rev.6A or Rev.8A. It's generic for A500/A600/A2000
