Control arm questions
 

Heres some pics of my control arm and bracket that bolts to the frame and crossmember..couple questions. 1st are all those shims on the uca normal, is that for alignment? should i reassemble the same way?
And 2nd you can see that there is a bolt missing in the bracket to the frame. it is the same on the other side. it doesnt exactly line up on either side, should i drill it out and bolt it up?

Re: Control arm questions
 

The shims are there for alignment... quite common on the C10s. It looks like somebody installed a crossmember from a later model... that would explain the holes not ligning up. Drill some holes and install the missing bolt while you have the suspension apart.

Re: Control arm questions
 

Looks like possibly a 71-72 crossmember.
(notice the steel brake line tab, on the front side of the crossmember)

I see the long rubber brake hose now connect through a hole in the frame,... similar to the 73-87 trucks.