I repainted the plastic dash area on my 68'(i know not the same) and used a scuff pad by 3M (used for bodywork:black in colour) lightly scuffed it up,then used a tack cloth and then painted it. Came out perfect! No "orange peel" The plastic on the 68' is smooth and not sure if there is any type of graining on the 69's (i owned a 69 with the dash having the burlwood inlay) and not sure how this will affect painting it.If so my advice would be to thoroughly clean the dash panel so there is no residue of any sort(grease,armour all,dust,etc...) so the paint will adhere to it and not flake or "peel". You are better off to take the panel out of the car to paint it.Hang it on some thing using a coathanger and just spray it from a distance of 10-12 inches.Spray in an even stroke pattern.Let it dry the time the paint manufacturer says to allow for drying and then repeat.You should have a nice finish now! As far as the chrome detailing on it,i know there is something out there for the 67-68 cars but not sure about the 69's? Anyways hope this helps and if you try my way,let me know how it works out for you.
David.