Heater Hose Nipple Size!

All, in the picture on the right you see what comes in a 70-74 small block heater hose nipple kit. It is 1/2 inch to 1/2 inch. However, the one on the left is the original one to the engine, which is a 73 340 by the way. It is 1/2 inch to 5/8 inch. It is from the original manifold that came on the engine from 73. I called the place I ordered it and they said that is what they are showing for a 70-74 small block. Well, it is obviously not correct. Has anyone else run into this and do you know where I can get the correct one? Keep in mind I would rather find what is in the picture as opposed to a Mr. Gasket or Spectre brand that uses a wrench to put it in place. I am putting this back to original appearance as close as possible. Any help would be greatly appreciated. View attachment 1715649085


The pipe thread should be 3/8" pipe thread...

Now what size nipple does that go to on the heater core... You match the heater core nipple size to the engine nipple size...

Some years had 5/8" inlet and outlet, and some had 5/8" inlet and 1/2" outlet on the heater cores...