Battery and Rear Bulkhead question

I was talking to someone last week and was telling him that I needed to fab a bulkhead because I am moving my battery to the trunk. He claims that if you are running an Optima battery you dont need to install a bulkhead. I tried to find this stated in the NHRA rulebook but didnt find anything stating this. Is this true or is he incorrect? Also while I am asking about the bulkhead what methods have you used in order to fab the one for your cars?
Thanks
Rod