I have a 66 that somebody has smoothed out the top of the dash.it has no dash pad and you can see where it looks like someone has filled in speaker grille.(center of dash)my question is are there supposed to be defrost vents on top of dash?where?

Todd. On top of the dash there are two heater outlets for the windshield. Each outlet exists of 2 slotted parts, 0.5 inch apart. Each part is 1.60 inch in width and 4.53 inch in length. The middle of the 2 parts is 18.90 inches from where the dash meets the window pillar and some 2.36 from the windshield. Each slot is created by pressing down the metarial 45 degrees down (towards the rear of the car).
In the middle of the ignition strip sits an A/C outlet if factory air.

thanks rusty 66 did you remember all that or did you go measure?thanks for the info.