My brush guard is the same way, 1/2" off, but towards the passenger side, so it is super close to rubbing the driver side by the headlight.
Since you'll be removing and replacing the bumper and probably adding skid plates, it doesn't matter much anymore. And weight savings!
Have you decided which steel bumpers to go with?
2005 G55k – Mildly Modded/Restored Family Hauler
2005 Volvo S60 T5 M66 – IPD DP, exhaust, sways, R-brembos, FC04A, KW V2
2007 FSAE Auto-X Racecar