Not sure about the damage... you'll probably just have to see if any problems develop later on. I would think the worst case would be damaged friction discs, requiring a rebuild. I kind of doubt it though. For a drain/refill you only get out around half of the fluid, so you should have a mix of fluids in there. If you want to completely remove the type-f, it may require changing the fluid several times in succession. It will be kinda pricey.