I ordered a front flex disc for my car and got a rear one instead so I figured I would replace both. I unbolted the rear flex disc and slid the driveshaft as far forward as possible but I could not get the shaft to drop. Does anyone know what I have to do - disc didn't look bad - is it going to be a big hassle to replace the rear disc? I'm wondering if I should just put it back together. Any insight would be appreciated.