It can be done but it is more than just plug in the later brake plate.
The original brake has 1 1/8 inch wide braking surface in the hub and straight pull spokes.
The later hub, for which the TLS is designed, has a 1 5/8 wide braking surface, and a verticle spoke flange with angled spokes. The flange also adds strength to the hub.
The TSL brake is designed for later fork bottoms - the slot on the brake plate does not offer safe engagement with the early A65 forks with full width hub. Either the brake plate needs the slot building up or the lug on the fork leg needs extending.
You can use the original hub but it is better with the later item.
It is worth the trouble, the brake is vastly improved over the original.
First photo shows the difference in lugs, early fork at bottom and TLS, 1968 type, fork bottom at top.
Second photo shows the slot on TLS brake plate.
Third shows up to 1965 type full width hub.
And last shows the 1968 on full width hub.