Also, 98+ conversions on '93-'97, you will have to modify the front cab mounts. Since the frames are wider on 98+.
Also, make sure to leave about a big finger width gap between the front of the fender to the top of the core support. Don't butt the core support to the fender, this will thro off the header panel and you will have a curved look on the grill/lights.
Don't ask how I know
I have 2000 front end on my 97, been there done that!