Hey Ken,
The early covers can be made to fit. One thing you have to have is the metal backplate that goes with, and all the little rubber doohickies to fit in the holes. Nice thing about the old covers is that they are aluminum. Any good polishing shop can make them look great without plating, and I prefer the shine of polished aluminum to chrome, personally. My valve cover is polished, and that's why I want one--to go with and make a set. You can also have them blasted with walnut shells, wire brushed, bead blasted--all sorts of different finishes.

The process for "chroming" your existing plastic cover is called vacuum-metallizing. This is how the industry has been chroming plastic stuff for ages now. Used to be very hard to find this process, but as restoration is chasing newer and newer cars, many plating shops now do it. I have seen advertisements for the process in Hemmings.

Of course if you do the cover, you have to cut out a hole where the cam gear is. Then you custom paint the cam gear and add stainless bolt and polished center washer. Bling!!!
Regards,
DS