Help me explain what he did wrong...

They make templates to insure proper installation angle.

 

Hard to see, but looks like the rods too long and slack needs to be tightened.

 

Does look that way, remeasure, cut if needed and adjust.

 

With the brakes release and truck secure from rolling
Take a 7/16 wrench and tighten the adjustment bolt at the bottom til it stops. Then back off 1 turn.

That will shorten the stroke

 

That will do nothing to fix it as the pushrod is cut to long. To set up the brake only needs to be backed off 1/2 turn and then check it. Haldex manual attached.
If you are unsure of anything get a mechanic to do it (not the same guy tho).

 

Yea well until he can get it cut, he can make that simple adjustment with a 7/16 wrench

 

I have matched the rod on the old chamber and screwed up. Went back and found the spring was broken in the old chamber. It would not push the rod all the way out.
Going by templates and such is best.