Can any one help with windows nt setup?

i have a problem where i want to Dual boot windows nt and windows 98, i already have windows 98 installed and want to install windows nt on top.
But i do all the correct things such as 3 boot disks and it says the partion is incorrect and cannot find the setup files even though when i made the boot disks it copies them across.
Can some body help as i am likely to pull my hair out and run rampage with a sharp knife around Oxfordshire!