Another cheap but useful junkyard upgrade.  These lights are a GM unit, found on fullsize trucks and Cutlass Supremes (and maybe others). 

They feature a light that unclips, and a spool that has around 15 feet of wire on it—enough to reach well around the back of the Jeep.  The light has a magnet on the back for positioning when unclipped, and when you’re done you just turn the gray crank handle to reel the light back in:

I have another one that I plan to mount inside the Jeep, on the passenger side in the “CJ6 space”.

These were ~ $3 ea. at the local “U-Wrench It” - heckuva deal!