My Actron still reads low (just tested it today, it dithers between 10-12 on the 6 cyl gauge. I think for fun I'll send it to Old Man Bob and see what he gets - you up for it there, Kontak?

Mine too. I set my mixture with a digital multimeter. You just have to figure out if the meter is reading open or closed. When cold my meter reads 35% (100 - 65) so I just had to keep that in mind to convert the settings (100 -) referenced in all the documentation. I can watch it warm up and kick into the warm cycle and it dithers nicely.

Starting in '81 something's changed in the guts of the ECUs.