The strut rods on a 67 Mustang regardless of Shelby or not would be bare steel. I start out with a unpitted pair and put them in a tumbler to make them look as new.ypu need to use a metal preservative if going that route. Stainless steel paint will put you on the right path to a historic look.
I don't have a tumbler and suspect that most restorers don't either, so I revert to bead blasting and a light phosphate and oil treatment. When I say "light", I mean the phosphoric acid is about half what is the recommended amount for the amount of water and "cook" the items in the acid bath for 1 1/2 to 2 minutes instead of the normal 10. The temperature is the same, 180F minimum (I like 195F), and the oiling is the same. For long items, I use an 18 inch long stainless steel fish poacher (e-bay, $20) and stainless tools to pick up the end sticking out and place that end in the bath, swapping ends about every 20 - 30 seconds. Strut rods should have a darker look as they were heat treated. They should not have a light metallic look surface finish. After the oil is absorbed or dissipates, that may take a month, you can apply the identifying paint (if any). Boeshield T9 is a good treatment after the identifying paint.
Jim