rgd1101 :
you mean like a bracket ?
https://www.newegg.com/Product/Product.aspx?Item=N82E16817979016&cm_re=2.5_to_3.5_converter-_-17-979-016-_-Product
Yeah, I figured that was the only way. I was helping my friend build his first PC and he had a 2.5 HDD and I had a feeling there would be no way of mounting it anywhere without a new bracket. For now it is just resting on the 3.5" bay but I advised him to pick up a bracket asap, as a HDD has moving parts and isn't a great idea to just leave laying around.
Computer booted and looked very nice tho!