We do not recommend melting the weights.
Check your local race rules to confirm what is allowed.
If attaching weights to the bottom of your car, verify track clearance before race day. Place racer on a flat surface and confirm there is a minimum of 3/8-inches between the bottom of the car and the surface.
There is too much weight in the rear of the car. Move the weights forward a bit, and retest the car.
Yes, holes can be drilled into the rear of the Funnycar Pre-Cut Design. Round Weights (P350) and Tungsten Cylinder Weights (P3914, P3915) fit a 3/8" cavity and Tungsten CoG Weights (P3918, P3919) fit a 23/64" cavity. The amount of weight needed will depend on your local race rules.