I struggled with removal of various plastic parts when I was soundproofing the car. I broke one of the threshold trim panels in the process. I finally came to my senses and downloaded the 2014 factory repair manual available in this forum. When all else fails, read the directions!
FSM will be your best friend in this case. It can be found somewhere on this forum, I just can't remember where off the top of my head. The A-Pillar is mostly pulling away from the frame but there's a clip in there that you have to snip off, it's a retaining clip to keep the pillar from flying into your face if the airbag ever deploys. My replacement pillar came with it installed.