1961 Dodge Meadowbrook wiring

Electrical problem
1961 Dodge Meadowbrook 6 cyl Two Wheel Drive Manual 0

I actually have a 1936 Dodge D2 sedan, 230ci 6cyl eng which I am in the process of rewiring. Its a positive ground car. My question is: when wiring accessories like the clock do I use the positive (red) wire for the ground or do I use the black to ground (from the clock). Anyother info on wiring a positive ground system would be helpful also.

Pete