I've seen kits for '69 or more appropriately have been told they exist. Not so for the '67 and '68. But I may be misinformed as I am relying on heresay.
1968 400 Coupe, verdoro green, black vinyl top 1968 400 Convertible, verdoro green, black top 1971 Trans Am, cameo white, auto 1970 Buick Skylark Custom Convertible 350-4(driver)