>But can I safely load a F microcode on a E1A drive?

The microcode name grouping would suggest Yes, but the FTP directory
fails to say definitively, being out of date.
Some customers who have applied it may be able to tell us.
Beyond that I'd pursue the avenue noted in the index.html file:
  "Please e-mail smfry AT us.ibm DOT com if you have any questions."
I would set upon that person to get the online information
boosted to currency and full usefulness.

   Richard Sims,  http://people.bu.edu/rbs