In my case it was 35mm and I was able to get a kit from a loan a tool program at my local Canadian Tire. 2005 Expedition Eddie Bauer AWD.
But I was referring to the hub being seized in the spindle. It is hard to hammer since the dust shield is in the way and is sandwiched between the hub and spindle. You can't really heat the spindle it since there is a foam anti-vibration/rattle piece on the dust shield would melt (well, I guess you could still heat other areas around it but I didn't). I hammered for a while hoping to shock it free, but that didn't work.
So I sprayed with WD-40 (nothing better around) and let it sit overnight. Then I put a jack on the threads to put some pressure at an angle on the hub (most of the suspension weight) and with a few hammer whacks it broke free.