I've dealt with this before, and I'm sad to say i've had to remove the trans with the axle intack to the unit, then deal with it on the bench. I'm not saying it's not possible to be succesful in removing it in the car. I'm assuming you have been beating and prying the sheeet out of this axle by now, which means that the clip is prolly in really bad shape now, so the only way you are going to win this battle is get lucky and replact the axle clip. Here's what i've done. First off don't be nice it's just a metal part and it doesn't matter it's just a car part. Pop your axle back into the transmission to make sure the output shaft is clipped in properly to the diff. now push get something like a pry bar to hold tension against the axle on the driverside towards the way you want it to go, now hold that tension and get a long punch or chissel and hold it against the metal part of the axle near the tranny and hit the end of the chissel as hard as you can with a hammer.
