This is what I did to install NT4 and Win 98, first I wiped out all partitions then I installed NT4 and I let NT make my partition in the setup. but I too only have SP1 so I heard from a reliable source that up until SP3 NT4 could only see 8 gigs of any drive but I have only been able to convert 4 gigs at a time to NTFS. After I convert that 4 gig partion to ntfs i install NT there.After the install is done I used fdisk on my win98 boot disk to make the rest of the drive into fat 32, and installed win98. After all of that I used a program called Select it and it lets you choose what OS I wanted to load. It is long and hard process but it works.
