The windshield fluid trick was among the very best!
I smile just thinking of it; and the better ones that got away!
There’s a fine line between exploiting holes in the rules and cheating.
NASCAR has a unique history of both. I think DW’s most well known was when his crew chief noticed that the rules defines the weight of a car at the beginning of the race, but made no mention of weight at the end. He outfitted the roll cage with a little door and filled the cage with led shot. This was at Bristol. During the parade lap, DW said “Tally Ho” on the radio, opened the door and dropped over 100 lbs of excess weight. Of course he won the race. Cheating? I don’t know. Smokey Yunich making a 9/10 scale race car, absolutely cheating.