I'm fairly timid about handling my own mods; I know my limitations and don't want to damage the car. If you're not comfortable with the work, you should listen to your instincts. While I enjoy the LED upgrade, it's not worth messing up the paint or plastic.
If you watch the video I linked at the 1:20 mark, it shows the 2 pins and the sockets they push into about a foot in from either end of the light bar. Those are probably the hang up. Mine popped right out with very little effort. Not sure you can get to them from the inside without major surgery. I had to get the hatch at just the right angle so I could pull the whole bar straight up from where it slots. The biggest issue I had was with the gasket. I had to slit it as mentioned in the install video. Also, I got very lucky and inserted the bulbs the right way on the first pass.
With all that being said, it is a nice appearance upgrade but really does nothing for the reverse lighting. The backup camera is still way too dim at night. The backup lights simply do not project sufficiently and the camera's sensor is pretty poor.