You can make a wire loom and heat shrink the connections. The solder joints are y connections (2 wires on one side and 1 on the other). Here is a really rough drawing. It was the best I could do from an iPAD. The red boxes indicate where the joint is and where to cover with heat shrink.
The picture is for the positive wire. On the negative wire you need to add a resister close to the base of the LED so each LED has a resister on it.
As you can see there are 9 wires for positive and 9 for negative. You have to make the wire short and carefully add to the loom. It takes some time to do.
When I had them all connected I used wire ties to attach it to the bottom of the light bar.
Here is what it looks like from the top.
Hope this helps. At least don't make too much fun of my drawing. :roll: