5 1/4" floppy on 4122

I'm trying to install an old TEAC 5.25" drive in an almost-as-old Compaq
4122. Holding down F10 on bootup and choosing "Computer Setup",
"Storage" shows that the disk is considered a 3 1/2" disk (Storage: A:
1.44-megabyte (3.5 inch)". Help (F1) says "By selecting the storage icon
you can display or change the configuration of your computer's diskette
and hard drives." When I do that, Help says Diskette Drive A: allows you
to specify the type of diskette drive configured as A: as follows:" and
a 360-K 5.25" disk is one of the options.

But I don't see any way to change to it. Anyone know about this old issue?

A little more: My Computer, Floppy Drive A brings up a "Disk in Drive A
is not formatted. Would you like to format it now?" Selecting "OK"
brings up a formatting menu with 1.44M 3.5" and 720K 3.5" offered as
options. Just to see what would happen, I chose 720K... but got the
proper error message that the disk in the drive was not that capacity.

--
--John
Registered Linux User #291592