The big ones can be heavy and hard to handle. Might be easier to just unlatch them, then go outside and lift the window with one hand and place the supports with the other. Yes do use silicone or 303 UV Protectant on the rubber seals or they can "bond" to the glass. Note also the latches are adjustable, should be snug enough to keep wind-driven water out but not overly tight so they are hard to use or stress the glass and seals.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
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