First, without the resistor there's a good chance you'll either overload the regulator and/or the PS AND possibly fry the LEDs.
Now, not knowing the resistance per foot of the cabling you intend to use, it might be that its resistance is sufficient. Just don't know.
Also in that vain, using just the diameter of the cable I can't reasonably guess what current level the individual wires will tolerate. You might be able to google the cable's model # (or whatever) and find its Ωs per foot.
All things considered, I think that if you start with the lowest possible voltage level and gradually increase it (if need be), you'll be able to observe the LED string's response and be able to better decide your next course of action.
Now, not knowing the resistance per foot of the cabling you intend to use, it might be that its resistance is sufficient. Just don't know.
Also in that vain, using just the diameter of the cable I can't reasonably guess what current level the individual wires will tolerate. You might be able to google the cable's model # (or whatever) and find its Ωs per foot.
All things considered, I think that if you start with the lowest possible voltage level and gradually increase it (if need be), you'll be able to observe the LED string's response and be able to better decide your next course of action.