You need both left and right hand calipers as the ratchet mechanisim is based on a one way clutch. In other words one works going CW the other workd going CCW.
Also the matching brackets.
If it stops raining I'll back the car out of the trailer try and get a couple pictures of how mine is mounted and the mods to the arms and bkts. These are just a small welded piece on each.
I also looked on Speedway and they have some instructions on the bleeding and residual valve issue. They say to remove the calipers and bleed them by pointing the bleeders vertical. You still need to tap on the caliper with a small hammer to shake the final bubbles out of the ratchets.