If you are going to change your wheels, go with a performance upgrade.
I would lose those heavy wheels to a forged Ford wheel or a Forgestar after market.
FORD RACING MUSTANG SHELBY GT500 REAR WHEEL | Part Details for M-1007-SA1910* | Ford Racing Performance Parts
Forgestar Wheels Custom Rotary Forged Flow Formed Concave Performance Wheels
I would lose those heavy wheels to a forged Ford wheel or a Forgestar after market.
FORD RACING MUSTANG SHELBY GT500 REAR WHEEL | Part Details for M-1007-SA1910* | Ford Racing Performance Parts
Forgestar Wheels Custom Rotary Forged Flow Formed Concave Performance Wheels