Dave ,
I have not run a tstat for years . Old motors ran cooler without plus not keen to get stuck in the lanes with cold motor and closed tstat .
As to old temps . Would normally run 155-175 on cool days and running down freeway . Once in middle of winter ran highway for 11 hours never got to over 130 , it was 0 celcius and lower most of that . Yes in traffic would slowly creep up , fans kept it under 210ish even in 40deg C (100F)
Now heats up quicker and runs about 185-190 on freeway . We are in winter here now so have not had real hot days yet .
Dragula , thanks . If I remember you have similar issues ?
I have the Mopar performance 5 blade clutch fan and a 12"manual control pusher fan , factory shroud on cross flow AFCO radiator .

Tex