here is my input. I do a lot of welding and bodywork. I agree with the inputs saying that they would do a series of tacks and blow them cool as you go. I think your idea of an ice bag is ok. Turn the hood upside down, place the ice under the hood and do the tacking; it couldn't hurt. My first thought is what caused the cracks? Bad hinges can place stress on that area and do it. The hinges on my 69 cuda were worn out to the point where i had to pull down pretty hard to close the hood. The bushings were worn out and the hinges flexed outward. I found a place that rebuilt my hinges and they work great now. Sms at 1-800-989-6660.
