Sharpen the back (untoothed) edge of a scrap blade on a grinder - a file will do.
Holding the forks in a vice, tap gently with a hammer, easing the sharpened tip of the hacksaw blade in between the dimple and the fork. This is done gently all around the dimple, until the blade digs in and starts to raise the dimple. Keep working around the dimple, not in one place.
When the dimple has moved out a tiny bit you can work the hacksaw blade in a less sharpened area of the blade, prising the dimple slightly more.
Eventually you will have the dimple out the thickness of the blade - then you can tilt the blade up and using the blade as a sort of chisel, ease the dimple some more. If you take your time, and work constantly around the edge of the dimple, eventually it will come out clean and undamaged.
The dimples an all Choppers are made from stainless steel, so cleaning them will be no problem. Solvol Autosol (or AutoChrome) on a rag wrapped around a small finger will soon have them gleaming like new.
Re fitting them is also fairly easy, when you have your forks back from the paint shop, loosely fit one dimple, then place the forks dimple side down onto something smooth and rigid.
Place the second dimple in the upturned second hole, and get a second person to support the forks, while you toddle off to find a hammer and a small piece of wood.
Place the wood over the top dimple and tap down with the hammer. The dimples will grip into the forks. Finish off by using a piece of aluminium to tap them fully home - a piece of wood will suffice.
Never be tempted to place the dimples in between the vice jaws and shut the vice - yes your dimples will go in nice and square and easy, but the vice jaws will leave cross marks in the dimples edge. If you do use the vice, cover the jaws with some cardboard at least.
If you damage a dimple (shame on you) they are almost impossible to find in bike shops, but they were used on many different Raleigh models over the years, so a donor set of forks should be available from your local amenities reclamation site (the tip).

This is what it would look like if you ever found a box of them in an old bike shop. Raleigh called them 'thimbles'. If you ever see them - BUY THEM ALL!!!