My car keeps over heating when I’m driving

If I am interpreting things correctly.

You have a 67 Dodge Dart with a 360.

I know the snout of the 360 aluminum water pump is linger than the cast iron of a 273, but I can not understand where your space went to.
View attachment 1715720074
Do you have stock motor mounts and transmission mounts and cross members?
This is the space I have. Less than 3 1/2 from radiator to pulley.

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