Someone was asking whether the spindles are similar for the AD and Taskforce trucks. I couldn't find the posting, but I have the info.
From 51 to 59, they are identical. I don't know what the difference is on the earlier AD trucks

This is from a Canadian GM parts book
group 6.020 steering knuckle

51-59 half ton forging 3708831 part# 3709756

Bob


55 Cameo 396 TH 400 with overdrive
65 Caliente conv
67 BB Caliente conv
67 Mercury 1 Ton
76 GMC 3/4 ton 454ci
84 Buick Turbo Regal