Got the M/75 in last night, ended up being the perfect purchase. The entire chassis is in the nicest shape of any of these laptops I've picked up. There are no cracks - in anything. It looks like NEC did a complete redesign of the 9.4" 640x480 LCD casing, adopting the hinge attachment method from the touch screen (far more sturdy and robust), and a new hinge. So very neat. Also got a different variant of the NL6448AC30 screen that has heavy industrial sheilding in back.
Issues - dead motherboard (the power board is FUSED to it - weird), apparently someone spilled something sticky on it, the screen panel has a short that causes it to cause the machine not to boot. But that's fine, I just put the guts of my other M/75 (the AAC) one in there, and it's running great, used the original CPU board though. It has a newer BIOS revision I can't find on the FTP that's Y2K Compliant - so I have one that recognizes 2021 - hehehe. Also, the rubber rollers inside the VersaTrak (Trackball) were split in half and rotting away, so I took some parts from the P/75's original Trackball and fixed that problem. It was a little jittery at first but it's starting to work better the more I use the laptop. Put Windows For Workgroups 3.11 on the original hard drive this morning. Came with 2 PCMCIA cards that work - one an NEC SCSI card, the other a V34 modem - no dongles for either, a 540MB HDD (the biggest on this series) and an official NEC 8MB memory card (so 16MB out of the box - I might swap with the 40EC). It also has the original battery - which I'll probably be replacing or putting new cells in.
Next up will be the NEC Ultralite PC-410 - a 25MHz 486 from the original run that has a screen and casing that's utterly destroyed. That comes in on Friday. No trackball, yellowed keyboard. My plan on that one is the 4MB Memory Card + one of the smaller HDD with FreeDOS on it. I might be using the M/75 screen housing on this one with the older hardware, and either find the short in the one panel, or replace the circuit boards in the other panel to get a working display.