pspence, Welcome to the forum.

I think that you're facing a drop out width difference. Your rear drop outs are probably 126 mm wide and you're installing a hub intended for 130 mm spacing. With the wheel removed measure the distance getween the inside surfaces of the rear drop outs to see what I'm referring to. Because the difference is so slight, many simply use their thumbs to spread the drop outs outwards and install the wider hub.

If the distance is less than 126 mm, you may need to cold set the frame and realign the drop outs. A 130 mm wide hub can also have the spacers replaced with thinner ones to be closer to 126 mm, but a redish of the wheel is required.

Brad