The 180B struts will need new cups put on them.
Get some old stanza struts, and neatly hacksaw the cups off, just above the weld bead. Then use the 1200 springs and 1200 strut top. I recommend using Stanza struts, as cup doners, because the cups are the same spring diameter as 1200, and the strut tube diameter is the same as the 180B. So they swap easily, the 1200 struts is smaller diameter, and fitting these cups to the 180B strut is difficult without a jig (which I have). Using the 180B struts requires fitting the Stanza lower arms.
The Verada/Commodore disc brake conversion is well documented on a fella called Cameron's (CM510) site, so I've not bothered to re-invent the wheel. MY 1200, My Brother 1600, and my Dad's AE86 Sprinter all use the same setup as my verada/commodore front brakes.
Click hereps. site is currently down search for CM510.
Regards,
Chris.