For what it's worth, I used a metal 'spudger' to wedge the springs in. In the beginning, I struggled with them mightily. Because I'm a hacker, I have a dozen or so of them lying around for various uses, mainly prying things open. Once I figured out how to use the spudger to wedge the springs in, it was smooth sailing (well, easier sailing, anyway). https://www.amazon.com/AKTOO-Spudger-Opening-Professional-Devices/dp/B0854G6XJN/ref=sr_1_1

Gotcha. That was the issue. Switching to No Line Ending fixed the issue. Thanks!

If you solder them into the other side, they don't clear a Raspberry Pi. I could bend them outwards though, similar to the FTDI connector, but it's a super tight fit between the frame and the camera connector on a Pi3.

Ah. I wasn't sure if my kit was a 'later version'. I was able to finish construction. The instructions on just how to mount the main board with a raspberry pi aren't very clear - I could not tell if the board was supposed to be mounted to the underside of the back pieces, or on top. On top seems to work so far.