I watched the RvGeeks video, then did my own easy DIY replacement project using these Amazon materials:
LED Strip Lights
LED Strip Connectors
Strips can be trimmed to size at the cut marks. Connectors make for very simple 12V wiring. And as WindsorBill cautioned, I cut out and removed the original fluorescent ballasts. (Whether you bypass or remove the ballasts will depend upon your particular fixtures -- do what's easiest for you.)
As I recall, it took me about an hour to convert six fluorescent fixtures.
I also converted all my 12V halogen fixtures using these:
LED replacement bulbs -- Pin type
And I swapped the 12V incandescent bulbs with these:
LED replacement bulbs -- Wedge type
The only caveat is these non-fluorescent bulbs
do not dim. But who cares? I never used the dimmers anyhow.