Nice mods you are doing on your Leo so far, with great pictures & explained steps to go along with them!

As Airbrushler pointed out, I had done a headlight mod to my HL KV-1 earlier back in March this year, & at first I followed a very similar order of steps in making mine as you have, but after making them several times, I would now have one small suggestion to alter the steps for anyone converting their Heng Long lights, which differs from how you currently show finishing your lens.

Rather than wait to make the line patterns on the lens after I had already heated the plastic, pressed the shape, & made the lens curved, I found it was easier to score those lines on the plastic with my razor knife, using a ruler or straight edge, while the plastic is original & still flat, before it's heated & pressed into a curved shape. Doing the steps in that order you can more easily make very straight lines that are evenly spaced, & get an even cleaner production look to the lens. I also pressed the lens so that the scored lines were on the inside of the lens too, this way the lines can be seen but not felt on the outside of the lens.

~ Craig ~