I'd agree with what Dan said. Your picture doesn't' show any evidence of an attachment point for the brake drum on the transmission output shaft yoke.
Check the pics on this post for what the transmission mounted brake would look like.

Check your rear brake backing plates for signs of a lever or cable attachment point which would indicate wheel mounted parking brakes.

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.