I had it running fine, until the backlight broke. The trick is to compile
  a kernel for the boot floppy that ignores the density check and just returns
  as a 1.44Mb device.

Yes, I already figured that out.  Now I'm getting far more frustrating
results.  I've tried eight times to run the install script, and each time it
fails in a new and exciting way.  Sometimes it just hangs at random points.
Sometimes it can't mount wd0a just after mkfs.  Sometimes it can't mkfs.
Sometimes it unpacks everything, but when I try to reboot, wd0a is garbage.
Every time it fails, it scribbles on the boot floppies and I have to make
new ones.

I always set the "water faucet" to "maximum drip," but it seems to reset
itself at random intervals.

Any suggestions?