I have a toploader behind my 289... Came with the car.
I thought I would be swapping it out for a WC T-5, but nope... It's not gonna happen.
The toploader reminds me of the Muncie M22 I used to have in my 69 Corvette (both shift like butter, but the toploader is WAY quieter
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)
with 3.31 gears out back, I can 0-60 in first gear (4.79 is my best so far, according to my Speedhut GPS speedo
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), and I can still cruise in 4th at 75mph, turning 2800rpm, and getting 20+ mpg... It's true love.