What is the best way to get an overdrive auto in a 67 Barracuda?

My painter put a GVOD behind a 727 in a 69 Barracuda Fastback. Minor clearance with a hammer. Said it fits better with a 727 than a 904.
I don't have any personal experience with these guys, maybe someone here has.

This is what I would like to go in our 69 Barracuda Fastback project.
We have a ways to go...
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