318 Running Richer w/ Carb Swap

I have not replaced it myself and it looks like it's been on there long enough to say previous owner had not either. Would a stock mechanical pump really put out more pressure than needed? I have one on the shelf that I could swap if need be, but I'll fuel pressure check to the troubleshooting list.
I have seen new stock replacement pumps put out north of 10#. You will never know until you test it. It's all part of the diagnosis. Make sure the
tune-up is correct. Like Rusty just mentioned. Check the timing.