Thank you all for your suggestions!

My P475 is slowly making progress toward netBSD usefulness.

I've been using booter 1.11.1, and walking my way down the
kernel releases to find an older one that works. With GENERIC-47
I at least get a different error. repeated scsi device timeouts
messages followed by hang. This must have something to do with
my driver. The A/UX partition I'm trying to use lives on a Syquest
EZ135 cartridge. Whenever I reeboot after one of these netBSD hangs,
durning my normal MacOS Startup sequence, it drops into macsbug
with a messege "looks like silverlining was trying to load" Silverlining
is the name of the control panel which deals with the EZ135.

So now I'd like to try seeing if I can get a kernel to work without
a root drive. By using the MacOS file option of Booter. But Booter
won't load kernels that are in the format they come from directly from
downloading. (ie GENERIC-47) But I can't un zip or untar them. What do
I have to do to them to make them useable with the MacOS file option of 
Booter?

Thanks,

Joe