Tip #1: unless his user name is Rusty Rat Rod, don't listen to the guy at the parts store.
Tip #2: if you have an aftermarket anything, even if it's an OEM replacement, don't expect it to fit right up. Aluminum radiators are near the top of this list.
Tip #3: take the hose you have, and get lost. Lost in the parts shelves at the auto parts store, that is. You know what you need, you now have a handy reference, you'd be surprised how close you can get from there.