I have a one owner '69.
My upper control arms were bare. I cleaned with Evapo-Rust. For high humidity like here and FL, brush on Rust Cure or similar phosphoric acid solution, scrub with green Scotch Brite to remove black rust and other discoloration left by Evapo-Rust. Wipe off within minutes after scrubbing. Dry 1-2 days. The appearance should be very close to original stamped HRPO sheet steel. Apply RPM.
After awhile, if any rust re-appears re-apply phosphoric acid, scrub and re-wax.
Lower control arms: you can use Resto-Rick's cosmoline in a rattle can. Be sure to catch all drips - you can combine leftovers 50-50, more or less, with mineral spirits until the color doesn't show much and apply to UCAs and other bare stuff about once/year, but not on fresh wax.
Torsion bar adjusting bolt is clear zinc plated. Its swivel is phosphated.
Spindles, drag link, tie rod ends, Pitman and idler, and strut rods were drop forged, not cast. Forgings are hot worked in dies while red or yellow hot and end up with dark mill scale, a non-red iron oxide, which gives a blue-black color when new. Check out the color of fresh forgings on new suspension parts. You can get close to this color with gun bluing. Or if you are using new parts on your car, leave them as is. Parts of forgings were machined, and those parts should be bare metal. Use the Google custom search feature at the top of this page to find discussions on using gun bluing on restoration parts. After bluing, use RPM. I don't think every forging was the exact same color, so variation would be a good thing. Follow up with RPM or dilute cosmoline.
Sway bar links and washers were phosphated.
Sway bar and brackets were either dipped or sprayed with black enamel. The flexing of the bar in normal use causes the paint adhesion to fail, so a remedy might be to spray with plastic bumper additive to make the paint flex too.
Strut rod large front washers were clear zinc plated.
I too am not sure about whether original black tie rod sleeves were painted or phosphated. Anyone know?
