You need to find where the grub screws in the cross slide would adjust the gib strip - I can see two likely suspects in the first image, but normally there's more. I'd look on the tail-stop side of the cross slide - many bits on that lathe look similar to a ML7, and that's where the gib screws are on the ML7.

On my ML7 I *think* (too wet to go check) there're 6 holes - three to locate the gib and three to tighten the gib, fairly evenly spaced along the length of the dovetail. There's generally dimples machined into the mating face of the gib strip that the locating grub screws screwed into the cross slide fit into to stop the gib sliding about, and then the main adjusting grub screws then apply pressure onto the gib strip to mate to the face on the dovetail. If you look on the top slide you can see 4 grub screws to adjust the (shorter) gib for the top-slide.

That same image - the gib strip just looks like there's no locating dimples in it - that might be a decision that you have to take whether to sanction adapting the gib strip to allow the locating holes for the gib screws.