computerguy08, Yes, "standard" XT BIOS never supported floppy larger than 360Kb DS/DD .
You need a 1) real 3" 360Kb floppy drive(rare) 2) "generic" floppy controller and 3) real DS/DD 5" diskette.
Another option is to use a 1) Hi-Density XT floppy controller with onboard floppy BIOS
2) 5" or 3" Hi-Density floppy drive and 3) 5" or 3" Hi-Density diskette.
Look to the "Floppy Disk and Serial controller" as an example
http://www.malinov.com/Home/sergeys-pro ... c-and-uart
Your "UMC I/O card" seems contains a Hi-Density Floppy controller.
All you need is a "Floppy BIOS extension". You may find one at
http://www.minuszerodegrees.net/rom/rom.htm
and select any "floppy" BIOS i.e. from DTK.
You may also use a Gotek floppy emulator with Flashfloppy firmware
and 360K image.
Another option is to use any form of XT IDE (full or XT CF Lite) and make
a bootable HDD or CF.