I thought 185 was a bit steep
In TCR mode I've been using 125 recently so I tried converting that in the same way
"Temperature (degF)","Electrical Resistivity"
68,1
200,1.09166666666667
300,1.16111111111111
400,1.23055555555556
500,1.3
650.381679389313,1.40443172179813
800,1.50833333333333...