I'm basing my comment on my experience with converting our 70 Dart to power. The manual coupling was much larger dia. on the splined shaft. Thankfully I had the other coupling with the power box! Others experience may vary.
Understood. My most recent was a few years back. Went from column shift manual steering to floor shift power steering, column, shaft and all, so I wouldn't have even noticed a difference there. Bolted right in. Good luck to all.
