From that angle the tank looks stock but of course the colour is not. Petcock is on the correct side, you are missing the molding on the edge of the tank. There is no lock on the gas cap, only a latch. The 500 was produced in three colours, brown gold & green & all had black inserts painted on the tank with pinstriping. Red/burgundy colour was used on later 550's I beleive. Here are examples of the 500 in candy gold & green.