Ahoy Johnny
What i did with my rag-top is install a flouresent type tube inspection lamp its clamped to a cross member with strong cable ties fed to a switch on the dash.
I find its handy as its wether & bash proof and can be removed if in the ecvent of a mishap at night requireing a inspection lamp - the light is a typical fluresant blueish light.
Into the payload i have a cheap & chearful 21w reversing light fixed perminantly to the rolll bar, pointing at 45deg down into the load area - more than enough light.
on the rear i have the obigatory 55w "work lamp" hardly ever used but handy when cuppling a trailer in the dark