Oswald - Using jimgmc's "GMC" bushing part number, these appear to be NOS Bushings that will give you the exact part needed. The listing says $15 USD for a pair of bushings (1 shackle) with 8 sets of bushings available. Best of luck sir with your search sir!
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~ Dan
1951 Chevy 3 window 3100
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"My Grandpa Carl's Truck and How it Became Mine"
1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver)
US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)