Hi Bruce (eveyone) The Series I cars were originally painted with an Alkyd Enamel. They were cellulose based (vegetable oil) and required lots of EPA unfriendly solvents to spray. Also not very durable by todays standards they get brittle with age. The Series II cars and forward were switched to an Acrylic Enamel. Only the Silver and Dark Blue were "metallic" colors on the Series I cars - and thus the only one's to receive a clear coat. That was because the metallic particles mixed in the color coat could wind up on, or very near the surface of the enamel paint - that would leave them exposed to the atmosphere and leave a rough surface - so a clear coat was necessary to both seal the metallic particle in, and provide a smooth surface that could be polished etc. (this is no longer a problem with modern Acrylic Urethanes - they can be sprayed in a single stage without the need for a clear coat). If you are using a modern Acrylic Urethane Enamel (single stage-two component type paint).. there is no real "need" to clear coat it. However it can be clear coated to enhance gloss, allow higher degrees of buffing and many clear coats enhance UV protection. An Acrylic Urethane with a clear coat - you might call a "two step" pain job (I suppose). But don't confuse that with a "two stage" paints. With two stage paints a color coat is applied, and it usually sprays out semi-gloss to semi-flat, then the second stage is to spray on a catalyzing top coat - that chemically bonds with the color coat - and leaves a high gloss surface. I used PPG's - Deltron DBU (Deltron Base Urethane) on my 904 White 72 - everything is a trade-off of some type. My painter likes this product, has been using it for decades - it holds up well in the Florida Sun, and in case of an accident, it's a little easier to spot or blend in. My white 72 is my main "driver" in that I drive it to most Z Car Events, and on longer road trips. It isn't a Concours restoration... See: <a href=http://www.ppg.com/cr-refinish/phase1/frmHome.asp TARGET=NEW> PPG's Auto Refinish Page</a> FWIW, Carl B.