Well, I took one step forward & two steps backward. I removed the entire window frame by removing 20+ square drive screws & laid the entire thing on a picnic table. After close examination, I realized that the are 2 screws on each side of the frame that hold the center brace in position. That brace is the female section of the 'C' Hinge, & needs to have one side removed in order to slide the male section on the egress pane into it. In order to loosen that brace, I needed to remove the fixed panel from the top of the window frame. Using a heat gun, I was able to slip a blade in between the glass & the adhesive gently prying up. As I moved along the bottom, I slid a flat bar into the gap to prevent the adhesive from reattaching to the glass. I worked up both side & started across the top. When I thought I had the pane loose from the adhesive I attempted to lift the fixed pane gently, but I had no more bars or flat screwdrivers to insert & the adhesive had re-adhered to the glass. BLAM! The entire upper pane exploded as tempered glass will do. Now I'm screwed. The good news is, that I was able to use the heat gun to loosen the copious amounts of silicone on the screws & frame, so that I was able to slide the egress pane back into the female hinge. The BAD news is that the upper pane is not available from Hehr as a stand-alone item. I need to have an entire new window manufactured. I contacted Pelland Enterprises, a California company that sells Hehr windows. The rep will send the information to the manufacturer & get back to me with a quote. Can't wait to see what THAT'S gonna cost. Bottom line, if you're gonna attempt to do this, take your time & do NOT force the window from the adhesive compound. This might better be left to a professional, but if you're more careful than I was, you can be successful. I don't know what to tell you to use for adhesive to re-secure the fixed pane. Right now, the window is back in the wall with a lovely piece of 3.5 mil plastic covering the hole. It's held in by the inner frame & duck taped to the egress pane.