Aluminum polishing is cheap to do but labor-intensive. You can buy a buffing wheel for your 1/4" drill at any hardware store, which will also probably carry jewellers rouge in a variety of grades. Put down some double-sticky tape to hold the cover in place on a board or bench and start in buffing. The thing will be shiny again in an hour or so. To keep it that way, wax the part occasionally. Good exercise....
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.