Well, poor blistered fingers. You were right to boil the tires. It's really the easiest way to get them on the rims. You can try putting the rims into the freezer to enable easier fitting next time. The tires you use are good but might be too grippy to enable a nice drift. Check your LHS if they have either the HPI T-Drifts or Tamiya Super Driftech. Both are good for concrete grounds.