So i would be needing the kernel sources that John used for his posted testing iso. I used the kernel syssrc.tgz from here: ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-9.0/source/sets/ Kernels compiled with this source will not work with the mach64.
I used netbsd-9 from the day that I made the kernel. 9.0 is from February. If my kernel worked, then just getting netbsd-9 and updating SSIZE should work. Or, like Martin suggests, try -current :)
John