I used a pair of players, but put some wood along the channel to spread the force out. ( a
paint stir stick busted in half ,on either side) On the second window I remembered where my sheetmetal vicegrips were ,and used those. Once I had it bent a little bit(where it didn't flex back) I used an awl to pop it out at the end while flexing the channel a bit more. Then I just grabbed the end and pulled it out sideways. The frame bent back into shape no problem, since I didn't have to bend it too much in the first place...
Good luck.
I felt like I cheated since I have all the tools ready and never used most of them.