Sorry if my post has confused you a little
It's a kind of generic guide to adjusting the handbrake of a road going vehicle fitted with a conventional rear drum brake set up.
That said, it is applicable to the Ford Sierra.
Didn't know you were in the process of just rigging it all up
All you can do for now is roughly adjust the brake shoes & find the correct length for the handbrake cable.
First, wind the shoe adjusters out untill the rear wheel locks.
Yes they are the little cogs that you can see through the drum back plate.
These should be quite easy move by levering with a long narrow flat bladed screwdriver.
You may find that on one side you may need to lever the cog upwards & the other side the cog needs to go downwards.
Once the rear wheel is locked, back off the adjust a couple of clicks. ( This can be a bit tricky as some auto adjusters have a non reverse tab fitted & this will need to be one side to allow the cog to back off )
Tricky but easily done once you get the knack.
Once done, the brake shoes should be roughly set & you can now turn your attention to the handbrake cable.
If using a sierra cable, there should be a plastic adjustable section in the centre on one side of the cable & just a plain fitting the other side.
The adjustable part is there to remove the slack in the cable once it has been shortened to the approximate length.
Don't know how you have shortened your particular cable though so it is very difficult to give you the best advice