While I could get the striker spring and guide held back adequately… and the back extractor pin depressed a bit… the slide plate would not budge. It’s like it is “stuck” due to being out of tolerance when installed and “hammered in” or some such thing. I have no idea why it would be stuck in the channel so firmly. If I use a small screwdriver to try and get it started… (by prying in between the plate and slide… I’m sure to mar the slide).

I give up