I'm with these guys, bolt it on for fit and any prep that needs to be done. Also you might have it baked @ 190 degrees for a few hours before you have it finish prepped and painted. This will insure that the fiberglass is fully cured and you won't get dimples showing 6 months later in the finish.
I have always liked the classic cowl hood. Not so much of a cowl that it throws the look of the truck off. Post pics once you have it painted and installed!