My house is built with Metal Window frames.

I want to put 2 Double Hung Windows side by side in the same opening.

I can order a Vinyl piece to slide between the 2 windows.

My question is how do i brace the Vinyl piece between the windows so there will be no movement between the 2 windows.

Can i put a screw in the Head & Sill of the window next to the middle piece to make it secure ?