Use a short piece of brass or piano wire to connect the ground throw to the switch’s throw bar. I can’t remember how HO scale ground throws are built, but I think you will need to turn the ground throw around so that instead of the end with the peg facing the switch, the end with the hole faces the switch. If the end has bot a peg and a hole, ignore that advice. Bend up both ends of the wire such that the ground throw is now the distance from the switch that you want it to be when installed. Insert one bent up end of the wire into the switch’s throw bar from the bottom. This may take a little wiggling. Cut off the peg on the ground throw. Center the points and center the ground throw then place the ground throw’s throw bar over the other end of the wire so that it sticks up through the hole in the ground throw’s throw bar.

Another possibility is that since there is a bit of overrun in the spring loaded ground throw’s throw bar, you might be able to simply mount the ground throw a little farther away from the switch.

I’ve included a photo of the ground throw end of my arrangement. Since I can put additional spring into my linkage wire I use O scale ground throws. You should not do this. I do it because they are easier to get my fingers on and the long linkage can require a little extra throw due to flexing.