First of all, I hope the pics work. If not, I will fix and re-post.
This post documents a low cost way to add a lat machine to an existing power rack. I did this about 10 years ago, and it hasn't hiccupped once.
You will need:
Power Rack (duh)
Hardware - Buy quality hardened, bolt snaps are bad
Steel stock, 1 1/4 x 1/8 thick, about 8 ft should do it.
Square tubing for the upright. Larger tubing for the slider.
Pulleys - I used Marine grade from a boat store.
3/16 plastic coated cable, about 25 ft.
Various hardware for the cable ends (can't remember what these are called.)
snap links to combine cables, attach lat bars, etc.
A good drill
A NEW bit or two.