Robert Swinney wrote:
All replies suggested methods of moving the hole over to the proper
location. Of them, the drill jig was best. However, the OP stated he had
already drilled the hole through in the wrong location. So, any attempts to
"move" the hole over, even slightly, will enlarge the hole. That may or may
not be critical to the finished product.

A method that works well is this: Drill out the mislocated hole to the next
size machine screw tap drill diameter. Drill the tap drill hole for a
tightly fitted machine screw, say 75% threads or so. Run a bolt in the hole
and cut it off on both sides so that it stands "a fraction" proud of the
hole. Using an anvil and ball peen hammer, upset the bolt on both sides
such that it expands and locks itself well into the threads in the hole.
Now, go back and accurately lay out the center pop mark for redrilling the
hole in the right location. You don't want to repeat this procedure, do
you?

This sounds like the approach I'd take if I
didn't have a mill. Just be sure the screw
is mild steel and not stainless.

I've watched a real machinist handle this problem
in AL tooling plate. He bored a much larger hole,
perhaps 3/4" on the center of the correct hole, but
large enough to completely cover the area of the
wrong hole. He then made a plug of the same
material a couple thou over and pressed it in the
big hole. Then he drilled and tapped the correct
hole in the center of the plug.

As close to a perfect fix that you could get.