Attached is a pic of my upper radiator hose. Note the thermostat end is bigger than the radiator end. This is not just stretched to fit on. It is literally bigger on the one end. I measured the thermostat outlet and the radiator outlet and then went down to a local "hard parts" type auto supply store (not a chain store like Kragen, etc). They sell Good Year hoses and have a full catalog with a pictures and dimensions section as well as by "application" section. I looked up the end dimensions I needed and then went and looked at a picture of it. Low and behold, there was the perfect hose, just a little too long on one end. I trimmed down the long end and she went on perfect.
For the bottom hose, I'm am using a standard 6.1 Charger hose. It is a bit too long for my narrower car and dimensions, so I went with an aluminum, nippled splice tube from a hot rod shop website I found. The splices come in different lengths, depending on what size you need.
Hope this helps those of you still struggling with the different sizes of outlets found on these engines vs. the radiators available for these cars and/or conversions.