Hello Dmitry
I no longer have my Seal 28 and have no photos left, but I will try to describe how the spray hood on Aztec was fitted.
The spray hood was supported by 2 hoops of stainless steel. (they were originally aluminium but I had new stronger and larger ones made)
The larger hoop had fittings on the ends suitable to fix to the 2 raised attachment points with the screws as in your first photo.
The smaller hoop fitted to the larger hoop about 15 to 20 cm from the base of the larger hoop.
Before fitting the small hoop to the larger hoop you must first feed each through the corresponding channel/pocket sewn into the spray hood. (unless you have a pocket which is fastened with a zipper or Velcro. See below assembly.
There was a small aluminium channel which was attached to the coach roof and ran around the curved front of the cockpit combing. There was a rope sewn into the bottom front edge of the spray hood which was slid through this aluminium channel, a bit like a sail guide on the mast or boom.
Assembly
As far as I can remember the order of assembly was; fit the spray hood into the aluminium channel, then fit the smaller tube into the top front pocket which runs across the top of the spray hood just above the windows, and then finally the larger tube was fitted into the pocket at the rear of the spray hood.
I hope this helps.
Mike
Mike Edwards
Seal 28 "Aztec"