Looking at your picture, the left bracket (in the pic) iws actually the left mounting bracket. In the picture , it's also upside down and backwards.
The large hole mounts on the rear shock stud. Hold it up to the bike. It all becomes clear.
I can see your dilemma. I'd simply go to the Markland website or call them. They're a good company and will help you. You email them a photo, they recognize which model and email back installation instructions.:readit:
yes now that you added the pic we can try to help you.
It seems that you have all the parts, as glhonda sead the bracket mounts to shock mount,
I would think the backrest mounts to any of the small holes in bracket (as in your pic lower holes, in my pic upper holes) you have 4 positions to mount the rest to depending on how far forward or backwards you would like the back rest to sit.
any more questions? I'll keep watching this thread for a few days.
If it's like the 83 1100, the brackets get clamped to the frame under the seat.(I haven't seen the 1200 mount)
BTW, posting to an old post that doesn't answer your question gives less results. Better to start a new post.
Mines a bit different but it still bolts up simular to how yours does on the top shock bolt. Here's a pic. After you take a look at this remove your seat and see if it's not a bit more clear as to how it bolts up...
In your picture, the brackets are correct, you just have them on the wrong sides. As I stated earlier, remove the seat, remove the nuts securing the upper shock mounts. The bracket with the long ear with a small hole in it mounts on the left side as tricky stated. It mounts with a spacer and a longer bolt, not directly to the battery box.