4-speed o/d swap

The reason that I asked the question is I came across this when gathering info prior to my swap. Now they might be talking about 6cyl, I don't know, the article didn't specify.

(For bell housing clearance reasons, the small 124 tooth flywheel must be used on both the 1964-66 bell housing and the 1975-81 Overdrive A-833 bell housing. Larger 130 tooth and 143 tooth flywheels do not fit these bell housings the starter will not engage ring teeth).