100% hand drill...
I used two different cutting bits -- things with a long shaft which branches out into a flat blade at the end. *I dunno what they're really called. *It has a point past the flat blade to get the hole started.
You have to have one the size of the outer diameter of the jack. *The other needs to be the same as the thread diameter.
I totally guestimated the depth, but it turned out fine. *
If you look at the way the jack is on there now, you'll see what I'm talking about. *There's a central hole which is the same diameter as the threads on the jack. *Then, there's an outer recessed hole to mount the head of the jack flush with the body.
Basically, you do the same thing, but at an angle and cut the bigger hole about an inch deeper than the one you have now.
Just don't take the big hole all the way thru, or the jack won't have anything to grip... *I went a little too deep on the outer recessed hole, cuz I had a burr or something which wouldn't let the jack go all the way in - nevertheless, I didn't go "too far" cuz it's pretty hard to mess it up.