Lift and Turn Latch install for slide out

[ev372]

Hello everyone,
I have a 2005 HW 256 with the old style screw on handles for the slide out dinette, and I want to up grade to the Lift and Turn Latch. The black knobs were replaced with wingnuts by the previous owner. I need some photos of how the latches interact with the body of the camper. Mounting the spring latch on the slide out flange is not an issue, its how does the latch hold on to the frame/body of the side wall? The body flange is solid from top too bottom on my HW-do i need to cut and opening in the body? If anyone has the newer lift and turn latches and can send some photos of how the latch locks/secures to the frame, I would greatly appreciate it.