I picked up a '96 P38 HSE with 176k for the 4.6 to go into my wife's D2. Good fortune shined on me because I bought it without hearing it run (rotted fuel lines on a northern truck). The Reader's Digest version is I got it fueled and it runs great. While the 4.6 sat on a engine stand for swapping over the Bosch bits I noticed all the signs of a rebuild (bonus points here!). I decided to pin the liners since I was there. It was with some initial trepidation that I drilled the 7/32" holes into each liner and tapped to 1/4-28. A quick measurement revealed .3" hole depth. The liner thickness is approximately .150" thick. I ran over to Graingers and picked up some 1/4-28 x 1/4" SS cap head bolts. These were cross drilled for lock wire in the Bridgeport. I installed them with red loctite and never worried about protrusion because these sit recessed about .050" from the interior surface while the .10" insertion into the liner would be more than enough to keep things in place. I used an extended 1/16" drill bit (for flexing) to drill holes into the adjacent block webbing. Falling back on my days of lock-wiring hardware on too many navy weapon systems I secured the bolts in place although the likelihood of the red loctite failing is minimal. All in all, it took about an hour to complete the task.