Clear over Base. Basecoat is the paint, which requires a Clear Coat (Lacquer) to be applied after, to provide Gloss and Protection. Most popular and most likely if you car is a metallic.
2K Acrylic provides gloss direct from the gun and therefore does not require Clear Coat after. However this paint requires an activator/hardener for the paint to dry. Solid colours (not containing particles such as metallics) are available in 2K Acrylic, rarely can you get metallic and mica colours in 2K Acrylic. (Contains Isoc
For Classic Cars, Cellulose does not require a lacquer for gloss, or an activator for it to dry. It will need flat and polishing to bring a gloss effect. NOT ABLE TO MAKE FOR VEHICLES AFTER 1979.