Do the 318's have a rear main seal?

*UPDATE* Thanks to all who responded to my add. Yall helped me build some courage. I finally took the engine out of my 71 dart swinger with my dads help. I was really glad that we took engine out. We found a few bad freeze plugs and worn timing chain. We replaced the following parts Freeze plugs, timing chain, fuel pump, oil pump, water pump and all gaskets and seals were replaced. Engine was painted Chrysler blue. I finally turned it on and it runs good.