The problem with antique registration in Montana (and this wasn't made clear on the state website) is that you can only drive an antique to and from parades and

The problem with antique registration in Montana (and this wasn't made clear on the state website) is that you can only drive an antique to and from parades and/or car shows. I had originally planned to register it with antique plates because it's more affordable than a standard registration. That was a deal breaker though.