First of all, I sell a lot of putty, but it is hard to control the temperature of your car as it rides around the world getting to the destination.I have just seen a few cars not make it down the track because the putty melted and got onto the wheels.
I use a 3M tape that is good for extreme temperatures both hot and cold. Then I put tiny tungsten chips on one surface and it runs at 1 gram per 3 chips. Much more dense than putty. You can cut between them all the way down to a single chip if you want. When ready, peel the 3M backing off and place on the surface you want. The chips actually cost less than the putty in volume, and when placed on a clean surface are not likely to move without some prolonged force. These same chips are used on golf clubs and tennis rackets for balance and control, and they do Not come off with use.