That's weird because the big bearing and tie rod taper size increase was for 70 production other than the Boss cars which got them early.
I'd get in touch with Dan at Chockostang, he's the guru, and according to him, 69 drum spindles are the same as 67-68 drum spindles.
Therefore it follows that they shouldn't accept the big bearing or have the larger tie rod taper.
Do your spindles have the larger tie rod taper though?
I didn't run the number, so without doing so, my guess is what you have is for full size Ford.