This link has more info than you need to replace bulbs.
1966 Barracuda Instrument Panel Removal and Disassembly Photos
I didn't read it all. I dont know if he warned how easily the contact pins in circuit boards will bend, loosen and lose contact, or come completely out of the board. you can't be too careful.
The plastic bulb sockets have 2 tiny tangs holding them in place. They get brittle with age, those tangs break off. You can buy cheap sockets at ebay (5/8 is the size you need). OEM quality sockets will cost nearly same as the bulbs. 8 bulbs and sockets for my 67 panel totaled about 40 dollars.
