In the top picture your hub is oriented just about where it needs to be. In the bottom picture, the brake stay arm (the shorter, larger diameter link) bolts to the outside of the brake hub. You should have a shouldered bolt that passes through the backside (wheel side) of the hole in the brake hub (about 4 o'clock in the top picture). This shouldered bolt will also have a hole for a cotter pin to keep the nut from rattling off. The smaller diameter linkage, with the arm hanging off the back end, connects to the splined pin sticking out of the brake hub at 7 o'clock in the top picture. There should be a punch mark on the pin and on the brake arm to orient them correctly to eack other. On the other end of this same linkage, where it connects to the brake pedal pivot pin, needs to be rotated 180 degrees. If you already mounted the brake pedal (at the right footpeg) then you will need to remove the pedal, rotate the pedal pivot so the linkage connection is at about the 12 o'clock position, as opposed to the 6 o'clock position it is currently at (referring to the bottom picture). This pivot pin may have a punch mark on the end of the splined shaft that the pedal fits on to orient the brake pedal on the splined shaft, but I'm not 100% sure on that.
Here are picts of the axle components and spacers from one of my 750 K8's from another thread:
Fully assembled, sproket side:
Fully assembled, brake side:
Full assembly:
Fully disassembled. Parts from left to right:
-Left axle adjuster
-25mm spacer
-Axle (above)
-Sprocket carrier (above axle)
-42mm (32/33mm for 76' and earlier models) STEPPED SPACER
-Brake hub
-35mm spacer
-Right axle adjuster
-Axle nut
Reassembly, in order, from left to right:
Left axle adjuster goes on axle shaft:
Then the 25mm spacer:
Then the sprocket carrier:
THEN THE 42MM (32/33 mm 76' and earlier) STEPPED SPACER. This links the bearing in the sprocket hub to the bearing in the wheel hub:
Then the sprocket carrier fits into wheel hub:
Then the brake hub (no spacer here):
Then the 35mm spacer outside the brake hub:
Then the right axle adjuster:
Then get the biggest wrench you can find, and crank-er-down:
And putcherpantsbackon!