Transmission Recommendation for a 318

Proud owner of a '68 convertible project car and a stock /6 that we are going to replace with a v8. At the moment I have my eye on this particular engine ...

Complete rebuilt hot street 318 - auto parts - by owner - vehicle...

Hoping people have some thoughts and insights to share regarding an automatic transmission with overdrive to pair with it (opinions welcomed too). Would like to spin the tires once-in-a-while, but trying to keep the highway cruising RPM's down.