I have just committed both a kernel and a standalone device driver for TU58.
This means that it is possible to install a miniroot filesystem
from nine TU58 cassettes on 11/750, I will soon make the necessary 
files and upload then to ftp.netbsd.org.
NOTE THIS: Each received character from the tape generate a interrupt,
and if you are doing anything else on your computer (e.g. running
multiuser) then the device driver won't work.
NOTE 2: The kernel device driver _cannot_ write to tapes yet, and
I have no idea why. Reading tapes works well when running single user.
This means that installation tapes must be written under another OS.

-- Ragge