I've got an electrical engineering background and a LOT of 2-way radio installation experience over the past 48 years (since I was 18) and in my personal experience with installing ham and CB radios in many Jeep models, I really don't believe you will need to use RG cable for power & I don't believe power & ground wires would need to be twisted to cancel noise either.
Such techniques are sometimes needed for some installations but not usually for a modern Jeep.
When a CB is powered by an adequate wire gauge that is connected directly to the battery, noise is seldom a problem in a modern Jeep running the proper factory resistance style ignition wiring & resistor spark plugs as specified. Of all the CBs & ham radios I have installed into modern Jeeps, which is quite a few, none needed RG cable for their power connections or twisted power wiring.
The usual causes of noise in a CB radio are normally just from getting power from a random (noisy) power source, improperly/inadequate grounding of the antenna mount, inadequate wiring gauge, or someone having swapped the OE resistor type wiring & spark plugs for non-resistance or low-resistance ignition components.