I have used the Duplicolor single stage enamel with good results. It takes a few weeks to completely cure as I did not use a hardener (isocan's). I would not use a lacquer as this type of paint never really cures & is susceptible to solvents (eg: gasoline). So using a lacquer in the engine compartment & around the fuel door filling area is a bad idea. Also you cannot paint over lacquer with anything else. It must be completely stripped off to put urethane or acrylic enamels on.
Also the Duplicolor lacquers are a ready to spray mix. No reducing, no hardeners. For anything else follow the manufacturers directions for correct temp. range reducer, reducing mix ratios, adding hardeners & hardener to paint ratio. As in the case of the Duplicolor enamel I used it was a 4 paint to 1 reducer mixture as per manufacturers directions.