I decided it was a Really Good Idea, having proposed to make infrastructure for the the Poem Windows, to try out the system to make sure it would actually work like I expected. I bought a Geeekpi 7" 1024x600 display with Acrylic Stand and assembled it.
It arrived without instructions of any kind. There were 5 acrylic pieces, a PCB, an LCD, and a bunch of little nuts and screws and other things. I went to the Amazon page, where there were several pictures that were actually sufficient for most of the assembly. I discovered the hard way that you needed to get all the cables connected before trying to assemble the stand, but I had only been hooking pieces together very loosely, so it was not much work to disassemble and then reassemble the stand after everything was hooked up. The only really frustrating part was trying to attach the ribbon-cable video connector, which was not described anywhere nor clearly visible in the video.
Eventually I got it assembled and was genuinely amazed when I hooked everything together, powered it up, and it lit right up. And then turned off. I checked the connections a couple more times and then logged into the pi via ssh and un-commented the safe_hdmi directive to see if that would make it work. And it did! So from that point on, it was just a matter of getting the HDMI configuration right. Eventually, I found that there was a page with configuration information. The magic recipe (from that page) was
hdmi_cvt 1024 600 60 3 0 0 0
Voila! One Poem Window prototype, suitable for testing and display.