15x7 225/60-15 on front of Swinger?

Very nice!
That is the exactly the stance I am looking for
I am confused by backspacing. Would 4.75" backspacing bring the outer ring further inboard or outboard? What is the advantage of more or less backspacing?
I am running rear espo leafs in the stock location and will be installing QA1 large ball joint uppers on the front. I was hoping to run the 15x8's.

My current setup is this.. I am in the process of replacing / upgrading the front suspension.

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