A arms are same, you dont have to modify the holes for the balljoints, asd the casings are all same, just the stud length and diameters changed.
From 72 to 73 only the upper b-joints are different.
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-'77 Electra 403/TH350
-'76 GMC C-1500 Sierra Classic 350 4-bolt/TH350, 3.40 ratio
-'68 C-10 chassis
-'72 K-5 chassis
The designer of the #333882 head castings needs run over(edited) !!!
http://communities.msn.com/RandyR72K5
Randy
Lincoln, IL
"life's gonna leave me in the dust, if I don't try and catch up to it soon"
r72k5@hotmail.com