3 speed. Column shifter?
With your goals in mind, I would look for a running 318 / 360 equipped car or pickup with an auto in it as a donor. The 318 /727 in my 65 works out well. A B&M cable shifter makes the 727 work with minimal install effort.
Which brakes are you dealing with? Wife units need good brakes.
If you really like tire smoke, there is a rear end swap in your future. The 8.75 mopar is pricey, the 8.8 ford cheaper -but needs to be narrowed. Lots of ways to go, and opinions on the subject. Check the driveline forum on this one.
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