[flatheadron]

If you are truly in direct drive then there is a gear that slides into the planetary to lock the unit in direct. The overrunning clutch is locked out. If it still free wheels then I agree that something internal is not engaging as it should. I'll define freewheeling as no engine braking under decal and the ability to float when not accelerating, like an automatic does in drive range first gear. One thing I wanted to ask, you are not using a synthetic lubricant in the unit are you? there have been some reports that synthetic lubes will cause the overrunning clutch not to lock up. Nothing conclusive but something to consider. Even though Ford in the era said to use SAE 80 gear oil, Borg-Warner recommended SAE40 engine oil and cautions against using any type of hypoid oil. Back in the gear shops had a barrel of API GL2 or GL3 gear oil that was not hypoid (GL4 or 5) for use in manual transmissions. I recommend SAE 40 engine oil.