Cooling system has antifreeze in it now. Which is good, because by the
time I got around to plugging into the ECU and getting ready to start
testing stuff, both the air-temp and coolant temp sensors were reading
-1°C, and there was definitely a chill in the air. There certainly
wasn't a few minutes after firing the engine up, though: Air temp
sensor -- slung over the engine hump back panel, down by the gear
lever, because there's nowhere in the carby manifold for it to go --
was reading 25°C in pretty short order. I suppose, much like the song
goes: She's not too cold in winter, but she cooks me in the heat. 
Checked my sensor offset and whatnot, it's still where it should be, so nothing's moved there which is good. Engine and ECU are on the same page; locked timing at 10 degrees puts me right on the 10 degree mark on the flywheel.
For some reason, the engine now loses rpm sync when the revs drop below about 700-800-ish. There also appears to be more runout on the front pulley (and the trigger wheel appears to be staying completely true with the pulley) than there was before, which is strange. I need to check on all of that, but it doesn't feel like anything's loose. Maybe it's always been like that, and the sensor's just been bumped further away while I've been wrestling radiator and pipes?
I'll have to get a proper datalog next time...
Oil
May have cured at least one of my oil leaks by, er... putting in some
missing bolts. Whoops. 
Still need to get another tube of sealant, and go sort
that pushrod cover out. And the rear main does appear to be wet, as
well, but I'm not terribly surprised by that; I'm just telling myself
it's because the truck is sat at such an angle without the rear
wheels, and it'll not be as bad when it's level.
Bodywork
Made a little more progress on bodywork; continuing the rebuilding of the passenger footwell. Next step is moving my way on outwards from there and putting in the underside of the vent duct that runs just forward of the footwell; thankfully I have the driver's side to copy because that's in almost perfect shape. The most critical part is getting the holes for the vent actuating lever drilled in the correct spot.
I've also got to hoover out a load of rust-flakes from there, too, and slosh some rust-killer down into the space between the support structures and the outer skin; try and slow down the rot in the spots I can't easily get to, before I repair what I can and slather the lot of it with paint.
If I get fed up with that, I've still got other stuff to work on. Trying to avoid the temptation to get distracted by starting on other stuff; even though I already gave in to a big one, what with getting the radiator in and all that. It was a good box to tick, though, because having the engine in and running is a powerful motivator. (Amusingly, the google photos app has a little "7 Years Since..." box up, showing the pile of spark-plug boxes from when I first got the truck and changed all the spark-plugs. My, how time flies...)
Still, plenty of bodywork to do... Ough.
Did also manage to cover everything in the entire unit with dust and
sprinkles of DBG paint cleaning up the passenger side floor-panel;
where I've repaired the little access-door hinge, and painted it with
that high-zinc primer. Next step for that piece is paint, and probably
some riv-nuts installed in the floor, since I have a few of those
knocking about...
Would quite like to have the passenger side of the cab finished up for Christmas, but not making any promises on that!