i had an xbit installed on a 1.0 before and didnt need to remove the solder before hand. never had a problem with that. i havent recieved my xapt3r yet, so i dont know wether you would need to or not, but i dont imagine you would.
what i did when installing the xbit, is used a sharp knife (really pointy) and put the tip in the middle of the points and turned it slowly to help put a spot for the pins to sit. that seemed to help.