Tried to send you this in PM, but, it won't work. Since you are not comfortable in doing it yourself, I'll post this for everyone else's benefit:
OK, let me walk you through it then. First, remove the motherboard from the case and also remove the bottom shielding. This will give you access to the underside of the agnus chip. There are two holes under the socket and you can use two unsharpened pencils to push the chip out of its socket, instead of using a PLCC puller from the topside. There is far less risk of damaging things by doing it in this fashion. Before you remove the Agnus, take a picture of its orientation in its socket. This is VERY important. On the actual IC, there is a DOT and on the motherboard, there is a big number 1. The dot MUST line up with this number 1 pin in the socket, or you'll damage everything when you re-insert the ACE.
To remove GARY, get yourself a PLASTIC SPUDGER TOOL identical to the one in this link (if you are not comfortable with or don't own a proper sized DIP IC puller):
https://repairpartsusa.com/nylon-black- ... gIWR_D_BwE
You can place the flat end between GARY and the socket, and slowly work it underneath the IC, side to side and pushing slowly forwards. Don't use a lot of force, as you will slip. Take your time and slowly pry GARY loose in this fashion. Some people use metal screwdrivers for this, but, I will tell you that many fail in their endeavor, slip, and cut a bunch of traces under the socket, leaving them with a now non-booting Amiga in need of trace repair.
As gary starts to lift in the socket, keep the spudger parallel to the socket -- don't angle it towards the board. As you work it forwards, the and the spudger gets further in between things, it will slowly lift things out of the socket. Be especially careful once you get to the last few pins, because if you slip, you'll bend or break them.
Now that everything has been removed, follow Jens reassembly instructions. MAKE NOTE OF PIN 1 on both the AGNUS and GARY (PIN ONE ON GARY IS THE SIDE WITH THE U-shaped indentation, and, the IC socket has this same pattern as well as the silkscreen on the board).
Hope this helps.