Stephen
You need to check whether or not the wheels have been keyed in place – if they have been correctly quartered and tried out with their rods this may be the case and makes the job more difficult and the wheels more difficult the reuse.
If they are keyed then I would take Eric’s advice and drill out the shafts
If they are not you could make up a split wooden collar that supports the back of the wheel close to the hub, mount the whole assembly vertically and try knocking the shaft through with a brass rod that is near but under the shaft size. When I had to do this job I preheated the wheels in boiling water to lessen the grip of any loctite that may have been used – they all came off OK
Tony