Wet_Boots, thanks for pointing to online Conduit Fill calculator.
I used this place to find ODiameters for THHN 90C wires:
For 8 AWG shows 0.212", for 10 AWG is 0.160".
Running online calculations for three 8 AWG and one 10 AWG results in:
The conduit fill is: 39.79%
Still not clear can I run more than three 8 AWG wires inside ½” conduit?
Or even your idea to run bare 8 gauge wire, can this be OK?
I just do not have room in my box to install ¾” metal flex cable, no open knockout available for this size.