As built, most large-block Guzzis (e.g. the Mille GT) have black plastic covers at the front of the engine that protect the alternator from the weather. You’ll see that most custom Guzzis have these replaced with nice shiny metal ones. The reason is not purely cosmetic. Firstly, the plastic ones are usually damaged; mine was – although it looked okay when fitted, one of the mounting points was cracked. Secondly, if you fit a crankshaft-mounted ignition sensor (as I had), there is often insufficient clearance. So, I bought a nice shiny metal cover. When I came to fit it, there was still insufficient clearance at the front of the crankshaft, so I also had to buy some spacers. It looks nice and neat now – but it is something extra to polish, I guess.