But Mike, that's so... (gasp!) ..illegal :-)
A mountlist basicly tells the OS what the device is and how to use it. You don't need to mess with that, unless you don't have HDToolsBox.
Which you don't, because you got Bench1.X. Bugger.
Err... That's a problem even if you'd remembered all you once knew I suspect. You need make a proper mountlist by hand and include full HDD parameters and stuff. Example:
DH1: device = scsi.device
Unit = 0
Flags = 0
/*! ReadOnly = FALSE */
Surfaces = 6
BlockSize = 512
BlocksPerTrack = 252
Reserved = 2
Interleave = 0
SectorsPerBlock = 2
LowCyl = 273 ; HighCyl = 4497
PreAlloc = 0
Buffers = 80
BufMemType = 0
DOSType = 0x444f5305
MaxTransfer = 130560
Mask = 0x7ffffffe
BootPri = -128
Mount = 0
/*! Bootable = FALSE */
/*# BootBlocks = 0 */
#
Note that this comes from OS3.9 and it's one partition ripped out of context. My guess is that scsi.device doesn't exist on WB1.2, so you need to replace that with whatever. DOSTYPE is wrong; you want FFS, I run SFS (atleast under OS3.9 FFS is: 0x444F5303). You want "mount=1" (auto mount). Max transfer should probably be decreased. Also: "Bootpri=10", "Bootable = TRUE".
To mount you write in CLI: "Mount DH0:"
Then you should be able to format it. Format is a bit bitchy about parameters. You need to write like:
Format DRIVE DH0: NAME "Hubba" FFS
@general public: Does he need to "Install" to make it boot?