I agree this was way too difficult, but I found a trick. First of all, with the wheel well arch molding, removing the fender liner is a lot more involved so I wanted to avoid that. I did it entirely from under the hood.
I drilled a small hole through the fin of the cap before I removed it and marked the position. See photo. Then I put a small wire through it. This is because as soon as you remove the cap, it will fall into the inside of the fender. The wire will allow you to fish it out easily. Then just pull the connector off the bulb with your fingers. I was able to remove the wire clip that holds the bulb in pretty easily with the long nose pliers.
Installing the new bulb, reattaching the hold-down clip, and pressing on the connector is pretty easy and fast. Again, the long nose pliers were the trick. The only hard part is putting the cap back on. Mark it before you remove it so you know how it aligns. It only goes on one way so you need to know how to line it up before you press it in. You can see the mark that I made. With a screw driver (a bent one worked best - like the one in the photo) I was able to press the cap on squarely (with fingers in front and screwdriver on the back) and then twist it by the fins. I removed the battery first to gain access. All in all, I think I could do it again in 20 - 30 minutes and only swear a couple of times. Yeah, it's absurdly difficult but this trick really helped.