Well, it took FAR longer than I hoped but the car is running again.
Things that got finished
-Rear seals done.
-Oil pan got the OEM seal I forgot I had. Straightened the flange braces a lot. If it leaks again I'll go full RT
-Replaced oil drain plug
-Cleaned up some glazing on the flywheel and pressure plate. Clutch seems to be working well
-Replaced throw out bearing while I was at it
-Removed transmission dust cover on the back that made removing the driveshaft difficult.
-Wiped down all oily surfaces including the exhaust, engine/trans plate, oil pan, trans crossmember, diff crossmember...
-Engine oil got Valvoline VR1 20w/50 for upcoming summer weather next time I drive
-Transmission fluid replaced with Ford Motorcraft XT-M5-QS manual trans fluid aka "unicorn tears" and very well liked in the Miata crowd. Supposed to be better than the redline MT90 I had before)
In progress or needing extra work
-Retorqued front crank bolt for now, but I think I'll have to replace that seal as well but it's only available online. I'll replace if necessary when I wire and properly do the electric fans
-New coolant overflow tank hasn't arrived but will install as soon as it arrives to get things tidier
-Waiting on a big C clip and wave washer so I can use the Nismo solid shifter. ISR shifter went back on with very light rtv for now. I plan on on somehow adapting the stock 240sx lower shift boot to the stock S40 lower shift boot bezel. Might require more printing or at least cutting from a sheet of aluminum or steel.
-Driver window either got misaligned or off the track when I was rolling it up today 😢 doesn't seem to go down without way too much force.
Little or no progress
-Haven't installed the AC bulkhead plate, but I think I'll have enough time to at least do the interior lines and install the plate. Will cover the openings for now.
-Still no radio/digital media receiver. We'll see if I can get something at least fitted to the console before I leave