Not concentrating and have managed to put mineral oil in my Hope Mono Mini Pro's! Yep it's started eating all the rubber already.
Anyone know if I'll have to rebuild lever and piston or just lever?
Link to the right rebuild kit would be useful!
Is it easy ish to do?

Change the lot, simply not worth taking chances with brakes. Assuming that bike calipers are pretty much like car calipers but smaller, it's very, very easy.

Did you only put in in the reservoir or did you bleed it thru with the mineral oil? Having said that calipers are very easy to rebuild. Hope website for vids I guess