The wrist pin on that engine is clamped tight by the split end of the connecting rod with the clamp bolt in it. If there's actually a wrist pin knock, its caused by the pin being loose in the piston, not the rod. Replace the piston/pin assembly.
Another possibility is the piston being loose in the cylinder, creating a "piston slap". That's usually a much lighter-sounding noise, though, a ticking type of noise as the load comes off the piston after acceleration, not during. If you've got cast iron pistons, there used to be a spring steel expander available from Perfect Circle that was placed between the wrist pin boss and the piston skirt with a special set of installation pliers. I haven't seen a set of them in close to 40 years.
Jerry
Jerry