I have to replace 3 failed units that are 24" x 36". I have already purchased replacements and removed the outside wood trim on the windows and broken one insulated glass free from the window opening. I got a sheet of small rubber pads with the glass and was told to use two at the bottom to support each glass. They also gave me a tube of sealant. My problem is " how do I support the glass in the opening while I reapply the wood trim to seal it." Should the glass be glued into the opening before attempting to seal the installation and if so what product should I use for this purpose?