Any guidance on my 1970 Duster plans

67~72 bars mount on the front of the K and are wider and pick up the LCA tabs outward and low toward the wheel

73~76 bars go thru the K and mount in the notch portion where they pass. they are narrower and pick up the tabs on the 73~76 arms in the near middle of the arm up higher.

aftermarket bars mount to the K and generally pick up to a tab that's bolted to the lower shock pick up, or they utilize weld on mounts specific to the mfgr.

what bar you run will affect what brakes you can run-- or how those mount.