What is the best glue to attach a wooden dash?

Properly prepared metal with a solid coat of paint.
You should try a small spot of contact cement to see if it peals the paint.
If it does, use construction adhesive
Spread it out like tile adhesive so you have notches and then squish the wood down to the adhesive so it spreads out.

Rich

Either will work just fine and would be my choices also. The contact will work better, it just has to be properly placed the first time. There is no second time. A waterborne contact will not peel the paint. The original formula contact, that uses lacquer thinner to clean up with, is still the best. Don't use it inside and try not breath much of it.

My wood dash only had double sided tape to remove vibration and the rest was held on by the components in the dash.

If the wood is very thick, the double sided tape isn't a bad idea, as it lets the wood contract at a different rate than the steel it's fastened to.

If it's very thin veneer, then I'd go with contact cement too.

Here is a picture of the back of a Wood Dash,
as it was removed from a car in the early 70's

This one was attached by double sided tape of some sort.


Click to view attachment