[Matthewt1970]

Caulk will shrink. Take a hammer and lightly dent the area where the hole is so there is a slight valley for the product to fill and bit into. Then use exterior grade spackle or even better would be bondo as was suggested above.

 

[Matthewt1970]

In your own words, if you did that I would fire you and keep a days pay. Most painting contractors I know would fire you and keep a days pay. There is a way to do things with pride and then there is half a** things.

You got a point there. Spray foam is nasty stuff to get on the siding of your house and never leaves a paintable surface.

 

[Matthewt1970]

We have used regular car bondo on wood with no problems. Your car does a lot of flexing so if it dopesn't flex, it would crack going form summer to winter or from the shade to the sun.