I had the same problems about 25 years ago when I finished the first restoration on my 69 340 Barracuda. It had an incorrect radiator. I had trouble finding radiator hoses. I made a rather detailed sketch of the area and sketched in what would fit (i.e. needed bends) and outlet/inlet sizes. Then I went to my local NAPA, and the guy let me go in back and just look through the hoses. I found two that would work. The lower radiator hose only needed to be trimmed a bit on one end, and the upper needed a bit of trimming on both ends. I wound up going to Topeka Belt and Hose and had a custom high pressure PS hose made. It was actually cheaper to do that than buy a new one that did not fit.
