GPS mounting question

I just got a Garmin Nuvi 250w and want to use the little smooth disk on the dash. The adhesive that came on it will not stick to anything. So I went and bought some Scotch double sided foam squares, that also will not hold it at all. I have a 2004 Jeep Cherokee that has kind of a hard foam dash. A lot of cars have this material as the dash. So what is the best way to get the little disk to stick on the dash without permanently damaging the dash? I will probably never take it off but it would be nice if it wasn't a problem when I go to sell the car.

Thanks

anyone?

On my truck I stuck the disk down by the sunglasses bin. It's down out of the way and looks more built in and the plastic in the area is smooth. If you are worried about damage then just use the suction cup on the window and slide it all the way down and back to it still rests on the dash.

The suction cup is much better. Just make sure you flip that switch or it will constantly fall down