Yes, lower offset will bring the wheel further out and higher offset will push the wheel further in. A 9.5" wide wheel with zero offset has a 5.25" backspacing.
As a point of reference, the Campi clones that many Pantera owners now use, are typically 17x8 with 22mm offset (5.375" B.S.) and 17x11 with 12mm offset (6.5" B.S.).
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