Ok. So with the meter showing 0.8 ohms when the probes touching, subtract that from all of the readings.
Lets go through the measurements with the adjusted readings see and what they tell us.
For reference
.............................Ign Start..Ign Run....Acc....Start
_______________ Brown,...Blue,....Black ,...Yellow
Back, Accessory Only..open, ...open, 0.0 ohms, ...open ..=> Correct and no resistance measurable
2nd, Off & Locked......open, ...open, ...open, ...open..=> Correct
3rd = Off......................open, ...open, ...open, ...open..=> Correct
Run position................open, 0.1 ohm, 0.4 ohm, ...open..=>Correct but resistance, especially in the Access circuit.
Start position............0.1 ohm ...open, ...open, 0.0 ohms..=> Correct although possible resistance to Ign Start
The connections are being made to the correct circuits and not shorting internally.
Showing 0.1 ohms on this type of meter and using probes doesn't neccessarily mean there is a lot of resistance. I might do a load test if switches are difficult to come by. But the 0.4 Ohms to the switched accessory feed is really high. If the reading is confirmed, that's definately a problem. Switched accessory ( Q2 ) feeds the radio, windshield wipers and washer, heater fan, turn signals and maybe A/C if so equiped