14" X 5 1/2" steelies hitting SSBC front disc calipers!

I found, and purchased, a set of 14" X 5 1/2" (sbp) steel wheels for the Dart GT. Pulled passenger front side Rallye (also a factory 14" X 5 1/2" sbp) and bolted the steelie on (snugged up by hand). Tried to rotate the wheel and discovered it hits/rubs the caliper. It appears I'll need to grind down the caliper(s) to clear the steel wheels. How much clearance do I need? Does the caliper move at all while braking? As always any guidance/experience is appreciated.