The interior lights that come with the Casita are … affordable. The switch mechanism is prone to wear and difficult-to-impossible to access for cleaning or updating. Amazon does sell some almost identical clones, but they suffer the same issue. I had a couple of leftover marine lights from the boating days, so I decided to see if they would fit. The stock lights are longer than the marine lights are round.
After drilling out the existing light by the doorway, I was happy to find that the round light covered the existing holes. My first marking of where to drill — the black sharpie marks shown by the red arrows– was a bit off. So I used a combination square to draw a pencil line and redid the holes. The carpeting on the inside cabinet walled pulled away pretty easily, so I was able to feed the wires and connect with WAGO connectors.
After cutting the old light out, I found there was sufficient ground (white) wire to fasten a WAGO, so I pulled the white out of the top and crimped an extension wire on. The carpet on the shelf was glued down well, so I ended up using a paint scraper to lift the carpet to get to the wires. I crimped on a marine grade heatshrink butt connector to extend the wire. It’s overkill for a trailer — the shelf is unlikely to be doused in saltwater –, but it’s the parts I had on hand. I didn’t have a matching white so I used the black I had and put white tape on the wire coming down through the hole. The light uses marine colors, red for positive and black for negative / ground, while the trailer uses residential black for positive and white for negative / ground.
The lights don’t match, but I expect the switches will last much longer than the stock RV-style ones.