The first step was to disassemble the door end of the GH, retaining all parts for potential reuse. I constructed a frame of pressure-treated 2x6s, with a 6x 5/4 base. I cut out the base frame of the GH and inserted the PT frame. The frame is set off-center by about 3' because only one side of the patio door opens. I used the cross support I had added (1” aluminum angle) to square the frame into the front of the existing gable. Pic 1
After fabricating an aluminum flashing for the top outer side of the 2x6 frame, it was inserted with the upright bars outside the flashing, which were shortened and bolted in place. The original cross pieces were shortened and bolted in place, without the door track. Pic 2
To serve as upright bars for the wood frame, the doors were disassembled and the uprights were screwed into the wood with stainless steel screws. Pic3
One was placed back to back to the reused door jamb. All parts were assembled, using sil foam to seal them to each other. pic 4
The rest of the job was cutting the glazing to fit and inserting it using clips, screws, and caulk.
Exposed wood surfaces were painted with an enamel, and the windows were cleaned.