I have 2 of these fluorescent fixtures in the Lance, they work great and give off lots of light but not really very energy efficient when boondocking. I looked at swapping in LED bulbs in place of the T15s but the bulbs were pretty expensive.
After doing some reading and research I decided to re-make the fixtures with LED strip lights. I found
this 5 meter light strip for $12 on Amazon, and got a bag of
solderless connectors. This light strip has defined cut points at every 3rd LED so you can make any custom length. The strip is also backed 3M adhesive tape so it's peel-n-stick.
I drilled out the pop rivets holding in the bulb holders and ballast and got down to the bare fixture frame. I cut the LED strip into approx 15" sections and used 4 strips per fixture.
The LEDs are covered in a rubbery plastic to make them waterproof, so you just need to clean off one end of each strip and clip on a connector. Wire to 12v and done.
Lights are slightly brighter than the fluorescents and not as affected by the cold weather. All in all was a very easy and inexpensive upgrade!