What subframe? These cars are a unibody... The main rail in the front clip that goes all the way to the front bumper cannot be removed from the car. The washers go in the strut tower, on the strut mount.
A car with a subframe actually has a half frame you can remove and the front end (body) will come off with it.
ClubGP:
There's a link to what they do.
Am I wrong? Someone else chime in if I'm not making sense.