Family and career commitments have kept me away from the bench lately, but the spark plugs are now all in and wired; I just need to tidy up the wires once the CA glue has set properly. The glue applicator tool was priceless here. I don't know how I managed without it all these years.
The original car had the wires from each distributor running through a tube, each wire exiting through an individual hole to its plug; I managed to make such a tube, using a 1.5 mm diameter brass tube and with holes drilled at the right points, but was unable to thread any wires through it except for those for the #1 plug, so I ditched the idea. Brownie points if you can spot the other error. And no, it's not the firing order, which I believe is correct assuming the distributor rotors turn counterclockwise when viewed from the back - as they are driven directly off the cams, which likely turn clockwise when viewed from the front, this is a good guess.
More family and career obligations are looming on the horizon, so I'll get back to this as and when I can.