You could install it under linux, under gentox. This is probably the beter route since the thing may run better. I have found a much easier way. BOCh for Xbox.
boch is a x86 emulator, there is a xbox port out for it. Thats right windows and evox on at the same time.
few easy steps
Mod your xbox, get evox running (there are tons of tutorials on this so i will asume you have read them)
get Bochs for xbox.
there is a detailed tutorial for boch for xbox in the tutorial section for emulators
Create a larger hd image for ddrive.img (about 2gb, more than 2 gb will not work.)
FDISK HD image with in Boch under dos (comes with boch, ready to go)
to creat one primary partition that takes up all space on drive.
hold l and r to get back to evox
rerun boch
make incoming directory in d
copy all the windows 98 files of cd in the windows 98 folder. never mind the other folders in there, the files in the root directory is all you need.
ftp the files (tons of ftp tutorials on this right here on the main site and forum.)
to the bochs folder (the one with that has the 1234.txt in it.)
run bochs, go to the d:\incomming directory ten run setup, or type the full path to setup then run setup.
note this will take forever to install but it will finish.
Don't expext windows to run smothly. the boch port for xbox can only emulate 32mb of ram. you can try changing this in the bochsxbox file but it will not load.
plus it the over head with the emulation.