Oh wow, I didn't realise nobody else had got a board to boot yet. If I'd known that I would have added a few drum rolls and embellishments to my story!
To be honest, since my SIMM sockets have the metal release tabs, you don't need much force to insert and remove SIMMs so the support tabs are not really essential as long as you take care to solder them down nice and tight to the PCB and obviously take extra care when swapping SIMMs. But I can confirm that both my donor boards and the RS Component sockets I mentioned seem to concur with the 9.6mm dimension but I take your point that not all vendors might be using the same spec. The part number on my donor board sockets is A-78985 3001-9007 but I can't find a match for that on the web.These are double sockets not singles though, and have plastic release tabs.
For the ADB sockets I have now ordered some new
TE Connectivity 5749181-1 from mouser because my donor connectors are a bit scruffy. I have also ordered
TE Connectivity 5749268-1 for the serial sockets. Mouser has PCB footprints available for these if you follow the links here. These are the parts from the SE/30 BOM spreadsheet. I do note that these have different types of support tabs so might need tweaked to fit.
Anyway, it seems rude not to post a couple of photos so here is a photo of my donor board before I started and later aborted repairs as there were just so many trace breakages and bad vias it was unviable. And of course a couple of photos of the new board in bootable but not yet complete state. My aim was to avoid installing any non-essential through hole components which would reduce access for any necessary rework to SMD components but I can go ahead and fit the remaining parts including the new connectors (ADB, Serial, PDS, DB-25, DB-19) which I'm waiting on arriving.
One last piece of advice I would give to anyone thinking of ordering some boards is to use the pick and place service for the passives on the bottom of the board. It'll save you hours and probably won't cost any more than sourcing the passives yourself. Unfortunately I understand (from this thread I think) you can only get this done for green PCBs not purple so it depends on preference. Besides that, ordering the boards from JLCPCB was trivial although I was relieved when they arrived and weren't inside out or upside down or whatever!
Note: The eagle-eyed among you might notice the unsoldered joint on my analogue board connection. I just noticed it myself! This is what happens when you work on projects until 3:30am. Will fix later.