First welcome to the site. Hope you find the support and information your need for your restoration needs
We've done this a number of times in other threads but not for 70 Mustangs specifically (that I can recall) so I've shared some of the basics below. Details above specific finishes (more in depth) can be found in other threads about suspension finishes and in the Library
To start out with none of the suspension items or steering is painted except for front sway bar. And you will find that natural finished is dependent (for the final look) on type of metal and how it was treated or handled after it was made (machined, heat treated, not treated .....)
Since you were specific to just suspension that keeps the list somewhat short so
Front suspension
Tie rods, idler arm, drag/center link, pittman arm, strut rods, spindles - all heat treated (range of darker tones with lighter machined surfaces and backing insert for tire rods.
Tie rod adjustment sleeves - Bare steel
Strut washers - will have color coding to identify their application
Sway bar end links & mounting brackets - Natural steel
Upper control arms - Bare steel main bodies with plated boot retailer, dark heat treated inner mount and ends
Spring seats - Bare steel main body with bushing insert with heat treated center rod
Lower control arms - Dipped black inner 2/3 (approx - at the stut rod attachment holes or near by) with natural ball joint ends. Plated boot retainer and dark heat treated ball joint retaining plate
Coil springs - Dark heat treated bare steel with identification stripes applied with a brush
Sway bar - Painted semi gloss black
Shocks - Painted semi gloss black
Steering box - Bare cast main body with natural stamped steel cover/lid with dark heat treated retaining bolts. Zinc plated end plug and machined upper main body, details with zinc plated upper nut. Typically with a number of identification and inspection paint marks. Rag joint shaft and mating plate, bare stamped formed steel and hardened rod and weld detailing.
Rear Suspension
Rear leaf springs - Dark heat treated leaf springs, held together by natural (non-heat treated) bare steel clamps with rubber insulators and separated with black plastic insulators between some of the leaves. Rubber eye bushings are natural steel and rubber.
Shackles - Bare untreated steel with heat treated rods.
Shocks - Painted semi-gloss black
Rear sway bar - If so equipped - Bare heat treated steel is what I've seen MCA rules want semi-gloss black.
Rear spring to rearend (shock plates) plates. Bare untreated stamped steel. Formed edges can be a little brighter due to the forming process
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All parts oiled to reduce rusting. Kept the details somewhat general we can steer you to more details answers in thread that focus on just one of two items but thought this would get you started. Of course some of this may come out in the follow up questions.
