I'll take flak for this, but the aluminum can be repaired with that aluminum solder stuff. It goes by many names, Luma-weld, etc.
You have to grind out the oxidation with a Dremel, then use a MAPP torch to heat the area and melt new metal into the divot. Sand or file smooooothe. Even if it is perforated it will fill gaps up to a quarter inch.
1966 109 5 door wagon 300Tdi "spermaceti fueled"
1994 RRC LeWiB "ruining the air behind me"
All my troubles are Rover