Finished on a transparent polymer water tank. I used a small butane microtorch (it was a bit windy that day so didn't help) to heat it up as it was the only thing I had on hand. This wasn't the best option as I think a heat gun, perhaps with a tinfoil "nozzle" to create less airflow, would have worked better. Clean crack and possibly mow. Heat the part to be repaired and slightly in the direction of the strip, it will become slightly transparent when it reaches the right temperature. Place the strip on the spot to be repaired and move forward. Plastic retains a lot of heat, so be careful not to overheat. Did what I needed and made a $250 plastic tank suitable for collecting rainwater for less than $5 in materials.