It's been half a decade since i pulled apart the beta live binaries, but here's what i remember. Don't take any of this as gospel: The beta live system has in-built protections to try and fool people into thinking the console went into an error code. The front lights start flashing, and the console appears to kernel panic. In reality, it's doing nothing of the sort. If you hook a debugger to the kernel, code still executes and you can pull back out of the executable. I never got very far in this process because i was unwilling to break the seal on my beta live kit to dump the kernel. My end goal was to get the soft mod exploit for Mech 'assult' to run on a beta live kit. IIRC, the beta live kits have a different signature key for saves too... Unfortunately, i owned the only known 'un updated' beta live kit in existence; it didn't have the 'xbox live' option on the dashboard before i manually updated the dash. I *really* wish i had taken an image of the hard drive first. I didn't realize what I had at the time.
There were at least 2 beta live kits that had the seals broken. The best chance would be to track one of those down and dump kernel/TSOP off of them. My beta live is sitting on the shelf next to me, but i'm still not really willing to pop 'er open. I had avalaunch running on the beta live kit at one point, but i still wasn't able to dump the chips. I wish i knew more about the whole Beta live program.
Yeah it's tough. I have two on the shelf now, but I know Im not the one to really rip one open, Id do more harm than good.