Ultimately agree with you. Its hard to get hardcore believers to consider other possibilities. Achillies has some good adivce. Your going to face a oposition of fundamental thinkers; thus, the only other way is to create a sense of doubt. I tried in the past to do something similar; however, I never have been able to make the case. Many Christians are stuck in a bubble; nevertheless, don't be discouraged by the sudden flux of opposition.