I cut the cable (this was a Raymarine radar
) leaving one piece long enough so that it would go from the radome on the mast down to the bottom of the mast. The other piece ran from the mast step aft through the cabin and ultimately up the pedestal guard to the display unit. I connected the two pieces of the cable using a junction box that sat on the bottom of the mast step.
Doing it this way meant I did not have to thread either connector through the mast or the pedestal guard.