Teardrops n Tiny Travel Trailers

I got the new rubber seals for my salvaged jalousy windows, I have the one window taken all apart, what should I use to seal the joints on the aluminum pieces? Also does anyone have any tips on how to undo the crimps so I can slide the new rubber seals in? the seals I speak of are called j-seals, and they slide into a small channel.
Thanks
Aaron