Perhaps a moderator will move this thread from "ENGINES" and into "Stock Suspensions + Bolt On Kits".
Given a choice, I'd rebuild the existing arms with fresh bushings (Polyurethane) and ball joints ESPECIALLY if you have forged arms instead of stamped, or stamped/forged end. The downside to the Poly bushings is that while the suppliers provide inner steel sleeves for the lower bushings, they don't provide the steel sleeves for the upper bushings--and they're very commonly rotted away with rust.
Photos of my '88 K1500 upper arm bushings.
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Although, on my '97 K2500, I put Moog upper control arms on it due to lack of time and enthusiasm to fabricate the steel sleeves.