type ascription issue passing in a sequence of resources into the resources method

I know this is more of a scala question than a gatling question, but figured it was relevant enough, and if answered would likely help others down the road. So the resources method in HttpRequestBuilder.scala does not use type ascription. as such in a method I have that will conditionally add resources I am unable to just pass in resources. How would I accomplish this?

def execute (callBack: => HttpRequestBuilder, resources:HttpRequestBuilder* ): ChainBuilder = {
  if(withResources){
    exec(callBack.resources(resources))
  }else{
    exec(callBack)
  }
  

}