The pan shape is the quickest way to ID but the 350 turbo will have a vacuum modulator at the right rear just above the pan rail, and the 700R4 will have a square four pin electric plug on the left side center. The later 700's have a round plug with 10(or 13) pins. If it has neither of these it's a turbo 400. Every parts store that sells trans filters and gaskets has a page in the book that shows pan shapes and the trans that has that shape. It's your best bet if unfamiliar.


Evan